Name: 1563-38-8|2,2-Dimethyl-2,3-dihydrobenzofuran-7-ol|97%
Brand: Ambeed
SKU: A148322
Price: 14.0 USD
Availability: InStock
Rating: 98 (29 reviews)

1
[ 1563-38-8 ]
[ 50893-53-3 ]
[ 101506-44-9 ]

Yield	Reaction Conditions	Operation in experiment
84%	With pyridine In dichloromethane for 5h; Ambient temperature;
84%	With pyridine In dichloromethane; water	23.a (a) (a) Synthesis of 1-chloroethyl 2,3-dihydro-2,2-dimethyl-7-benzofuranyl carbonate 21.5 g (0.15 mole) of 1-chloroethylchloroformate are added in a single portion to a solution of 2,3-dihydro-2,2-dimethyl-7-benzofuranol (24.6 g; 0.15 mole) in dichloromethane (150 ml). The mixture is cooled to between 0° and 5° C., and 12 g (0.15 mole) of pyridine are added dropwise. The mixture is stirred for 3 hours at 20° C. The organic phase is then washed with 2*50 ml of iced water. It is dried over magnesium sulphate and the solvent is evaporated. A yellow oil is obtained which is distilled. 34.1 g of the expected carbonate is then recovered (84% yield). B.p. 127° C./66.6 Pa (0.5 mm Hg).

Reference： [1]Barcelo, Gerard; Senet, Jean-Pierre; Sennyey, Gerard; Bensoam, Jean; Loffet, Albert [Synthesis, 1986, # 8, p. 627 - 632]
[2]Current Patent Assignee: AURELIUS SE & CO KGAA - US4725680, 1988, A

2
[ 1563-38-8 ]
[ 84428-21-7 ]

Yield	Reaction Conditions	Operation in experiment
95%	With potassiuim nitrosodisulfonate In ethanol; water at 20℃; for 1h;
84%	With potassium nitrososulfonate In ethanol; water for 0.166667h;	B.1 To a solution of 2,3-dihydro-2,2-dimethyl-7-benzofuranol (10.13 g, 61.7 mmol) in water/ethanol (7/3, 450 mL) was added potassium nitrosodisulfonate (Fremy 'USD salt, 48.26 g, 179 mmol) in seven portions. After stirring for additional 10 min, the reaction was diluted with water (-900 mL) and extracted with dichloromethane. The combined organic extracts were washed with water (400 mL), brine (400 mL), and concentrated in vacuo. Purification by flash chromatography afforded 2,2-dimethyl-2,3-dihydrobenzofuran-4,7-dione (9.23 g, 84%) as colorless oil.
	With potassiuim nitrosodisulfonate; sodium acetate; acetic acid In methanol; water at 25℃; for 1h;

Reference： [1]Tapia, Ricardo A.; Alegria, Luz; Pessoa, Carlos D.; Salas, Cristian; Cortes, Manuel J.; Valderrama, Jaime A.; Sarciron, Marie-Elisabeth; Pautet, Felix; Walchshofer, Nadia; Fillion, Houda [Bioorganic and Medicinal Chemistry, 2003, vol. 11, # 10, p. 2175 - 2182]
[2]Current Patent Assignee: QUEST DIAGNOSTICS INC - WO2006/66183, 2006, A2 Location in patent: Page/Page column 48
[3]Brown, Roger F. C.; Fallon, Gary D.; Gatehouse, Bryan M.; Jones, Christopher M.; Rae, Ian D. [Australian Journal of Chemistry, 1982, vol. 35, # 8, p. 1665 - 1678]

3
[ 1563-38-8 ]
[ 22128-62-7 ]
[ 132905-88-5 ]

Yield	Reaction Conditions	Operation in experiment
73.5%	With sodium hydroxide; adogen 464 In water; benzene at 5℃; for 0.666667h;

Reference： [1]Patonay, Tamas; Patonay-Peli, Erzsebet; Mogyorodi, Ferenc [Synthetic Communications, 1990, vol. 20, # 18, p. 2865 - 2885]

4
[ 1563-38-8 ]
[ 106-95-6 ]
[ 87386-25-2 ]

Yield	Reaction Conditions	Operation in experiment
97%	With potassium carbonate In acetone for 60h; Heating;

Reference： [1]Brown, Roger F.C.; Edwards, Gavin L.; Jones, Christopher M.; Rae, Ian D.; Teo, Peter Y. T. [Australian Journal of Chemistry, 1983, vol. 36, # 6, p. 1263 - 1273]

5
methallylpyrocatechol [ No CAS ]
[ 1563-38-8 ]

Yield	Reaction Conditions	Operation in experiment
84%	With iodine In dichloromethane for 0.5h; Ambient temperature;

Reference： [1]Kim, Kyoung Mahn; Ryu, Eung K. [Heterocycles, 1995, vol. 41, # 2, p. 219 - 224]

6
[ 1563-38-8 ]
[ 19810-32-3 ]
[ 222641-43-2 ]

Yield	Reaction Conditions	Operation in experiment
66%	With triethylamine In benzene for 18h; Heating;

Reference： [1]Keserue, Gyoergy M.; Balogh, Gyoergy; Czudor, Iren; Karancsi, Tamas; Feher, Andras; Bertok, Bela [Journal of Agricultural and Food Chemistry, 1999, vol. 47, # 2, p. 762 - 769]

7
[ 1563-66-2 ]
[ 1563-38-8 ]

Yield	Reaction Conditions	Operation in experiment
77%	With potassium hydroxide In ethanol
	With sodium hydroxide In water at 70℃; for 1h;	2.1. Reagents and solutions Solution 1.0 103 mol L-1 of carbofuran was prepared bydissolving 0.022 g of the compound in 100 mL solution of0.1 mol L1 NaOH which was heated for 1 hour in a temperatureof 70 C for the complete hydrolization of carbofuran tocarbofuran-phenol [32].

Reference： [1]Keserue, Gyoergy M.; Balogh, Gyoergy; Czudor, Iren; Karancsi, Tamas; Feher, Andras; Bertok, Bela [Journal of Agricultural and Food Chemistry, 1999, vol. 47, # 2, p. 762 - 769]
[2]Wong, Ademar; Materon, Elsa Maria; Sotomayor, Maria Del Pilar Taboada [Electrochimica Acta, 2014, vol. 146, p. 830 - 837]

8
[ 1563-38-8 ]
[ 358-23-6 ]
[ 308110-31-8 ]

Yield	Reaction Conditions	Operation in experiment
100%	With pyridine In dichloromethane at 20℃; for 1.5h;	15.1 Step 1: 2,2-dimethyl-2,3-dihydrobenzofuran-7-yl trifluoromethanesulfonate To a solution of 2,2-dimethyl-2,3-dihydrobenzofuran-7-ol (190 µL, 1.27 mmol) and pyridine (206 µL, 2.55 mmol) in DCM (1.3 mL) at 0 °C was added triflic anhydride (287 µL, 1.56 mmol) in DCM (0.50 mL) dropwise. After complete addition, the mixture was warmed to room temperature and stirred for 1.5 hrs. The reaction was then diluted in EtOAc (10 mL) and washed with 1 N HCl (10 ml), NaHCO3 (aq) (10 mL) and brine (10 mL). The organic layer was dried with sodium sulfate and condensed to yield 2,2-dimethyl-2,3-dihydrobenzofuran-7-yl trifluoromethanesulfonate (380 mg, 1.28 mmol, 100% yield) as a yellow oil. 1H NMR (500 MHz, DMSO-d6) δ 7.28 (d, J = 7.4, 1.2 Hz, 1H), 7.21 (d, J = 8.3, 1.3 Hz, 1H), 6.91 (t, J = 8.4, 7.3 Hz, 1H), 3.13 (s, J = 1.1 Hz, 2H), 1.45 (s, 6H). 19F NMR (470 MHz, DMSO-d6) δ -73.44 (3F).
	With pyridine In dichloromethane at 25℃; for 1h;

Reference： [1]Current Patent Assignee: PRELUDE THERAPEUTICS INCORPORATED - WO2022/35799, 2022, A1 Location in patent: Paragraph 0310
[2]Plobeck; Delorme; Wei; Yang; Zhou; Schwarz; Gawell; Gagnon; Pelcman; Schmidt; Yue; Walpole; Brown; Zhou; Labare; Payza; St-Ogne; Kamassah; Morin; Projean; Ducharme; Roberts [Journal of Medicinal Chemistry, 2000, vol. 43, # 21, p. 3878 - 3894]

9
[ 1563-38-8 ]
[ 109-64-8 ]
[ 250289-95-3 ]

Yield	Reaction Conditions	Operation in experiment
55%	With potassium carbonate; potassium iodide In acetone for 10h; Heating;

Reference： [1]Kossakowski, Jerzy; Hejchman, Elzbieta; Wolska, Irena [Zeitschrift fur Naturforschung, B: Chemical Sciences, 2002, vol. 57, # 3, p. 286 - 294]

10
[ 1563-38-8 ]
[ 3132-64-7 ]
[ 250289-99-7 ]

Yield	Reaction Conditions	Operation in experiment
80%	With potassium carbonate at 20℃; for 25h; Heating;

Reference： [1]Kossakowski, Jerzy; Hejchman, Elzbieta; Wolska, Irena [Zeitschrift fur Naturforschung, B: Chemical Sciences, 2002, vol. 57, # 3, p. 286 - 294]

11
[ 1563-38-8 ]
4,6-dibromo-2,2-dimethyl-2,3-dihydrobenzofuran-7-alcohol [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
83%	With bromine In chloroform at 20℃; for 1.5h;
83%	With bromine In chloroform at 0℃; for 1.5h;
67%	With bromine In chloroform at 25℃; for 2h;

67.3%	With bromine In chloroform at 0 - 20℃; for 2h;	2 Embodiment 2:4,6-dibromo-2,2-dimethyl-2,3-dihydrobenzofuran-7-alcohol (V) of preparation [0088]Take 1g raw material 2,2-dimethyl -2,3-dihydrobenzofuran-7- alcohol(IV) (6.0mmol) in soluble to chloroform (35 ml) and reaches 0 °C slowly sloly instillment liquid bromine (1g, 15mmol, 2 . 5eq)Removed ice-bath afterreaction at room temperature 2 hours. concentration and removal of solventafter obtain brown solid,column chromatography (dichloromethane as eluant)after get the product 1.4g, the yield is 67.3%.
45%	With bromine In chloroform at 20℃; for 1.5h;

Reference： [1]Tapia, Ricardo A.; Alegria, Luz; Pessoa, Carlos D.; Salas, Cristian; Cortes, Manuel J.; Valderrama, Jaime A.; Sarciron, Marie-Elisabeth; Pautet, Felix; Walchshofer, Nadia; Fillion, Houda [Bioorganic and Medicinal Chemistry, 2003, vol. 11, # 10, p. 2175 - 2182]
[2]Sieveking, Ivan; Thomas, Pablo; Estevez, Juan C.; Quinones, Natalia; Cuellar, Mauricio A.; Villena, Juan; Espinosa-Bustos, Christian; Fierro, Angelica; Tapia, Ricardo A.; Maya, Juan D.; Lopez-Munoz, Rodrigo; Cassels, Bruce K.; Estevez, Ramon J.; Salas, Cristian O. [Bioorganic and Medicinal Chemistry, 2014, vol. 22, # 17, p. 4609 - 4620]
[3]Jiang, Zhigan; Liu, Na; Dong, Guoqiang; Jiang, Yan; Liu, Yang; He, Xiaomeng; Huang, Yahui; He, Shipeng; Chen, Wei; Li, Zhengang; Yao, Jianzhong; Miao, Zhenyuan; Zhang, Wannian; Sheng, Chunquan [Bioorganic and Medicinal Chemistry Letters, 2014, vol. 24, # 17, p. 4090 - 4094]
[4]Current Patent Assignee: SECOND MILITARY MEDICAL UNIVERSITY - CN103254191, 2016, B Location in patent: Paragraph 0087; 0088
[5]Vzquez, Karina; Espinosa-Bustos, Christian; Soto-Delgado, Jorge; Tapia, Ricardo A.; Varela, Javier; Birriel, Estefana; Segura, Rodrigo; Pizarro, Jaime; Cerecetto, Hugo; Gonzlez, Mercedes; Paulino, Margot; Salas, Cristian O. [RSC Advances, 2015, vol. 5, # 80, p. 65153 - 65166]

12
[ 1563-38-8 ]
[ 107-04-0 ]
[ 104392-19-0 ]

Yield	Reaction Conditions	Operation in experiment
	With potassium carbonate In butanone at 80℃; for 22h;
	With potassium iodide; sodium carbonate In dichloromethane; ethyl acetate	1 Preparation of 2,3-dihydro-2,2-dimethyl-7-(2'-chloro-ethoxy)-benzofuran EXAMPLE 1 Preparation of 2,3-dihydro-2,2-dimethyl-7-(2'-chloro-ethoxy)-benzofuran To 100 ml. ethylacetate 8.23 g. (0.05 mole) 2,3-dihydro-2,2-dimethyl-7-hydroxy-benzofuran, 14.3 g. (0.1 mole) 1-bromo-2-chloro-ethane, 6.9 g. (0.05 mole) anhydrous sodium carbonate and 8.3 (0.05 mole) potassium iodide are added. The reaction mixture is heated for 30 hours and the reaction is monitored by gas chromatographic analysis. When the reaction is completed the mixture is cooled to room temperature, the solid is removed by filtration and the solvent is distilled off in vacuo from the solvent layer on a rotatory film evaporator. The residual yellowish brown oily part is dissolved in 50 ml. methylene chloride and washed with 5*30 ml. 5% sodium-hydroxide solution and water. The solvent part is dried above anhydrous sodium sulphate and the solvent is distilled off on a rotatory film evaporator in vacuo. 5.8 g. yellowish brown liquid are obtained and purified by vacuo distillation. The product distilled at a pressure of 0.2 torr. at 120°-125° C.

Reference： [1]Cuisiat, Stephane; Bourdiol, Nathalie; Lacharme, Vincent; Newman-Tancredi, Adrian; Colpaert, Francis; Vacher, Bernard [Journal of Medicinal Chemistry, 2007, vol. 50, # 4, p. 865 - 876]
[2]Current Patent Assignee: NITRO KEMIA IPARTELEPEK - US4668274, 1987, A

13
[ 1563-38-8 ]
[ 132740-43-3 ]
2,2-dimethyl-2,3-dihydrobenzofuran-7-yl 4-fluorobenzylcarbamate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
70%	With triethylamine In toluene Heating;

Reference： [1]Li, Weiwei; Blankman, Jacqueline L.; Cravatt, Benjamin F. [Journal of the American Chemical Society, 2007, vol. 129, # 31, p. 9594 - 9595]

14
[ 1563-38-8 ]
[ 3173-53-3 ]
2,2-dimethyl-2,3-dihydrobenzofuran-7-yl cyclohexylcarbamate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
69%	With triethylamine In toluene Heating;

Reference： [1]Li, Weiwei; Blankman, Jacqueline L.; Cravatt, Benjamin F. [Journal of the American Chemical Society, 2007, vol. 129, # 31, p. 9594 - 9595]

15
[ 1563-38-8 ]
[ 65535-53-7 ]
2,2-dimethyl-2,3-dihydrobenzofuran-7-yl 4-fluorophenethylcarbamate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
69%	With triethylamine In toluene Heating;

Reference： [1]Li, Weiwei; Blankman, Jacqueline L.; Cravatt, Benjamin F. [Journal of the American Chemical Society, 2007, vol. 129, # 31, p. 9594 - 9595]

16
[ 1563-38-8 ]
[ 54132-75-1 ]
2,2-dimethyl-2,3-dihydrobenzofuran-7-yl 3,5-dimethylphenylcarbamate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
79%	With triethylamine In toluene Heating;

Reference： [1]Li, Weiwei; Blankman, Jacqueline L.; Cravatt, Benjamin F. [Journal of the American Chemical Society, 2007, vol. 129, # 31, p. 9594 - 9595]

17
[ 1563-38-8 ]
[ 680203-71-8 ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 3 steps 1: K₂CO₃ / butan-2-one / 22 h / 80 °C 2: 18 g / dimethylformamide / 2 h / Heating 3: ethanolamine / 18 h / 20 °C
	Multi-step reaction with 2 steps 1.1: potassium carbonate / acetone / 48 h / 50 °C 2.1: potassium phtalimide; 18-crown-6 ether / N,N-dimethyl-formamide / 3 h / 50 °C 2.2: 2 h / 50 °C 2.3: 1 h / 20 °C
	Multi-step reaction with 3 steps 1.1: potassium carbonate / acetone / 48 h / 50 °C 2.1: 18-crown-6 ether / N,N-dimethyl-formamide / 3 h / 50 °C 3.1: methylamine / water / 2 h / 50 °C 3.2: 1 h / 20 °C

Reference： [1]Cuisiat, Stephane; Bourdiol, Nathalie; Lacharme, Vincent; Newman-Tancredi, Adrian; Colpaert, Francis; Vacher, Bernard [Journal of Medicinal Chemistry, 2007, vol. 50, # 4, p. 865 - 876]
[2]Sniecikowska, Joanna; Gluch-Lutwin, Monika; Bucki, Adam; Wiȩckowska, Anna; Siwek, Agata; Jastrzebska-Wiesek, Magdalena; Partyka, Anna; Wilczyńska, Daria; Pytka, Karolina; Latacz, Gniewomir; Przejczowska-Pomierny, Katarzyna; Wyska, Elżbieta; Wesołowska, Anna; Pawłowski, Maciej; Newman-Tancredi, Adrian; Kolaczkowski, Marcin [Journal of Medicinal Chemistry, 2020, vol. 63, # 19, p. 10946 - 10971]
[3]Sniecikowska, Joanna; Gluch-Lutwin, Monika; Bucki, Adam; Wiȩckowska, Anna; Siwek, Agata; Jastrzebska-Wiesek, Magdalena; Partyka, Anna; Wilczyńska, Daria; Pytka, Karolina; Latacz, Gniewomir; Przejczowska-Pomierny, Katarzyna; Wyska, Elżbieta; Wesołowska, Anna; Pawłowski, Maciej; Newman-Tancredi, Adrian; Kolaczkowski, Marcin [Journal of Medicinal Chemistry, 2020, vol. 63, # 19, p. 10946 - 10971]

18
[ 1563-38-8 ]
[ 928403-39-8 ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 2 steps 1: K₂CO₃ / butan-2-one / 22 h / 80 °C 2: 18 g / dimethylformamide / 2 h / Heating
	Multi-step reaction with 2 steps 1: potassium carbonate / acetone / 48 h / 50 °C 2: 18-crown-6 ether / N,N-dimethyl-formamide / 3 h / 50 °C

Reference： [1]Cuisiat, Stephane; Bourdiol, Nathalie; Lacharme, Vincent; Newman-Tancredi, Adrian; Colpaert, Francis; Vacher, Bernard [Journal of Medicinal Chemistry, 2007, vol. 50, # 4, p. 865 - 876]
[2]Sniecikowska, Joanna; Gluch-Lutwin, Monika; Bucki, Adam; Wiȩckowska, Anna; Siwek, Agata; Jastrzebska-Wiesek, Magdalena; Partyka, Anna; Wilczyńska, Daria; Pytka, Karolina; Latacz, Gniewomir; Przejczowska-Pomierny, Katarzyna; Wyska, Elżbieta; Wesołowska, Anna; Pawłowski, Maciej; Newman-Tancredi, Adrian; Kolaczkowski, Marcin [Journal of Medicinal Chemistry, 2020, vol. 63, # 19, p. 10946 - 10971]

19
[ 1563-38-8 ]
(5-cyclopent-1-enyl-pyridin-3-ylmethylene)-[2-(2,2-dimethyl-2,3-dihydro-benzofuran-7-yloxy)-ethyl]-amine [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 4 steps 1: K₂CO₃ / butan-2-one / 22 h / 80 °C 2: 18 g / dimethylformamide / 2 h / Heating 3: ethanolamine / 18 h / 20 °C 4: methanol / 15 h / 20 °C

Reference： [1]Cuisiat, Stephane; Bourdiol, Nathalie; Lacharme, Vincent; Newman-Tancredi, Adrian; Colpaert, Francis; Vacher, Bernard [Journal of Medicinal Chemistry, 2007, vol. 50, # 4, p. 865 - 876]

20
[ 1563-38-8 ]
(3-cyclopent-1-enyl-benzylidene)-[2-(2,2-dimethyl-2,3-dihydro-benzofuran-7-yloxy)-ethyl]-amine [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 4 steps 1: K₂CO₃ / butan-2-one / 22 h / 80 °C 2: 18 g / dimethylformamide / 2 h / Heating 3: ethanolamine / 18 h / 20 °C 4: methanol / 15 h / 20 °C

Reference： [1]Cuisiat, Stephane; Bourdiol, Nathalie; Lacharme, Vincent; Newman-Tancredi, Adrian; Colpaert, Francis; Vacher, Bernard [Journal of Medicinal Chemistry, 2007, vol. 50, # 4, p. 865 - 876]

21
[ 1563-38-8 ]
F₁₅₀₆₃ [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 5 steps 1: K₂CO₃ / butan-2-one / 22 h / 80 °C 2: 18 g / dimethylformamide / 2 h / Heating 3: ethanolamine / 18 h / 20 °C 4: methanol / 15 h / 20 °C 5: 7.35 g / KBH₄ / methanol / 4 h / 20 °C

Reference： [1]Cuisiat, Stephane; Bourdiol, Nathalie; Lacharme, Vincent; Newman-Tancredi, Adrian; Colpaert, Francis; Vacher, Bernard [Journal of Medicinal Chemistry, 2007, vol. 50, # 4, p. 865 - 876]

22
[ 1563-38-8 ]
[2-(2,2-dimethyl-2,3-dihydrobenzofuran-7-yl-oxy)ethyl]-(5-cyclopenten-1-ylpyridin-3-ylmethyl)amine [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 5 steps 1: K₂CO₃ / butan-2-one / 22 h / 80 °C 2: 18 g / dimethylformamide / 2 h / Heating 3: ethanolamine / 18 h / 20 °C 4: methanol / 15 h / 20 °C 5: 1.17 g / KBH₄ / methanol / 4 h / 20 °C

Reference： [1]Cuisiat, Stephane; Bourdiol, Nathalie; Lacharme, Vincent; Newman-Tancredi, Adrian; Colpaert, Francis; Vacher, Bernard [Journal of Medicinal Chemistry, 2007, vol. 50, # 4, p. 865 - 876]

23
[ 1563-38-8 ]
[ 583839-01-4 ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 2 steps 1: 83 percent / bromine / CHCl₃ / 1.5 h / 20 °C 2: 51 percent / CrO₃; acetic acid / H₂O / 1 h / 20 °C
	Multi-step reaction with 2 steps 1: bromine / chloroform / 2 h / 25 °C 2: chromium(VI) oxide / acetic acid; water / 1 h / 25 °C
	Multi-step reaction with 2 steps 1: bromine / chloroform / 1.5 h / 0 °C 2: chromium(VI) oxide; acetic acid / water / 1 h / 20 °C

	Multi-step reaction with 2 steps 1: bromine / chloroform / 1.5 h / 20 °C 2: chromium(VI) oxide; acetic acid / water / 2 h / 20 °C
	Multi-step reaction with 2 steps 1: bromine / chloroform / 2 h / 0 - 20 °C 2: chromium(VI) oxide; acetic acid / water / 1 h

Reference： [1]Tapia, Ricardo A.; Alegria, Luz; Pessoa, Carlos D.; Salas, Cristian; Cortes, Manuel J.; Valderrama, Jaime A.; Sarciron, Marie-Elisabeth; Pautet, Felix; Walchshofer, Nadia; Fillion, Houda [Bioorganic and Medicinal Chemistry, 2003, vol. 11, # 10, p. 2175 - 2182]
[2]Jiang, Zhigan; Liu, Na; Dong, Guoqiang; Jiang, Yan; Liu, Yang; He, Xiaomeng; Huang, Yahui; He, Shipeng; Chen, Wei; Li, Zhengang; Yao, Jianzhong; Miao, Zhenyuan; Zhang, Wannian; Sheng, Chunquan [Bioorganic and Medicinal Chemistry Letters, 2014, vol. 24, # 17, p. 4090 - 4094]
[3]Sieveking, Ivan; Thomas, Pablo; Estevez, Juan C.; Quinones, Natalia; Cuellar, Mauricio A.; Villena, Juan; Espinosa-Bustos, Christian; Fierro, Angelica; Tapia, Ricardo A.; Maya, Juan D.; Lopez-Munoz, Rodrigo; Cassels, Bruce K.; Estevez, Ramon J.; Salas, Cristian O. [Bioorganic and Medicinal Chemistry, 2014, vol. 22, # 17, p. 4609 - 4620]
[4]Vzquez, Karina; Espinosa-Bustos, Christian; Soto-Delgado, Jorge; Tapia, Ricardo A.; Varela, Javier; Birriel, Estefana; Segura, Rodrigo; Pizarro, Jaime; Cerecetto, Hugo; Gonzlez, Mercedes; Paulino, Margot; Salas, Cristian O. [RSC Advances, 2015, vol. 5, # 80, p. 65153 - 65166]
[5]Current Patent Assignee: SECOND MILITARY MEDICAL UNIVERSITY - CN103254191, 2016, B

24
[ 1563-38-8 ]
[ 99517-60-9 ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 2 steps 1: pyridine / CH₂Cl₂ / 1 h / 25 °C 2: Et₃N; Pd(OAc)2; bis-diphenylphosphinoferrocene / methanol; dimethylsulfoxide / 16 h / 70 °C

Reference： [1]Plobeck; Delorme; Wei; Yang; Zhou; Schwarz; Gawell; Gagnon; Pelcman; Schmidt; Yue; Walpole; Brown; Zhou; Labare; Payza; St-Ogne; Kamassah; Morin; Projean; Ducharme; Roberts [Journal of Medicinal Chemistry, 2000, vol. 43, # 21, p. 3878 - 3894]

25
[ 1563-38-8 ]
[ 38002-88-9 ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 4 steps 1: pyridine / CH₂Cl₂ / 1 h / 25 °C 2: Et₃N; Pd(OAc)2; bis-diphenylphosphinoferrocene / methanol; dimethylsulfoxide / 16 h / 70 °C 3: DIBAl / toluene / 0.5 h / -78 °C 4: pyridinium dichromate / CH₂Cl₂ / 40 °C

Reference： [1]Plobeck; Delorme; Wei; Yang; Zhou; Schwarz; Gawell; Gagnon; Pelcman; Schmidt; Yue; Walpole; Brown; Zhou; Labare; Payza; St-Ogne; Kamassah; Morin; Projean; Ducharme; Roberts [Journal of Medicinal Chemistry, 2000, vol. 43, # 21, p. 3878 - 3894]

26
[ 1563-38-8 ]
[ 38002-89-0 ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 3 steps 1: pyridine / CH₂Cl₂ / 1 h / 25 °C 2: Et₃N; Pd(OAc)2; bis-diphenylphosphinoferrocene / methanol; dimethylsulfoxide / 16 h / 70 °C 3: DIBAl / toluene / 0.5 h / -78 °C

Reference： [1]Plobeck; Delorme; Wei; Yang; Zhou; Schwarz; Gawell; Gagnon; Pelcman; Schmidt; Yue; Walpole; Brown; Zhou; Labare; Payza; St-Ogne; Kamassah; Morin; Projean; Ducharme; Roberts [Journal of Medicinal Chemistry, 2000, vol. 43, # 21, p. 3878 - 3894]

27
[ 1563-38-8 ]
[ 308110-32-9 ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 5 steps 1.1: pyridine / CH₂Cl₂ / 1 h / 25 °C 2.1: Et₃N; Pd(OAc)2; bis-diphenylphosphinoferrocene / methanol; dimethylsulfoxide / 16 h / 70 °C 3.1: DIBAl / toluene / 0.5 h / -78 °C 4.1: pyridinium dichromate / CH₂Cl₂ / 40 °C 5.1: n-BuLi / tetrahydrofuran; hexane / 0.5 h / -78 °C 5.2: 67 percent / tetrahydrofuran; hexane / 1 h

Reference： [1]Plobeck; Delorme; Wei; Yang; Zhou; Schwarz; Gawell; Gagnon; Pelcman; Schmidt; Yue; Walpole; Brown; Zhou; Labare; Payza; St-Ogne; Kamassah; Morin; Projean; Ducharme; Roberts [Journal of Medicinal Chemistry, 2000, vol. 43, # 21, p. 3878 - 3894]

28
[ 1563-38-8 ]
4-[chloro-(2,2-dimethyl-2,3-dihydro-benzofuran-7-yl)-methyl]-N,N-diethyl-benzamide [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 6 steps 1.1: pyridine / CH₂Cl₂ / 1 h / 25 °C 2.1: Et₃N; Pd(OAc)2; bis-diphenylphosphinoferrocene / methanol; dimethylsulfoxide / 16 h / 70 °C 3.1: DIBAl / toluene / 0.5 h / -78 °C 4.1: pyridinium dichromate / CH₂Cl₂ / 40 °C 5.1: n-BuLi / tetrahydrofuran; hexane / 0.5 h / -78 °C 5.2: 67 percent / tetrahydrofuran; hexane / 1 h 6.1: SOCl₂ / CH₂Cl₂ / 1 h / 25 °C

Reference： [1]Plobeck; Delorme; Wei; Yang; Zhou; Schwarz; Gawell; Gagnon; Pelcman; Schmidt; Yue; Walpole; Brown; Zhou; Labare; Payza; St-Ogne; Kamassah; Morin; Projean; Ducharme; Roberts [Journal of Medicinal Chemistry, 2000, vol. 43, # 21, p. 3878 - 3894]

29
[ 1563-38-8 ]
[ 308110-33-0 ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 7 steps 1.1: pyridine / CH₂Cl₂ / 1 h / 25 °C 2.1: Et₃N; Pd(OAc)2; bis-diphenylphosphinoferrocene / methanol; dimethylsulfoxide / 16 h / 70 °C 3.1: DIBAl / toluene / 0.5 h / -78 °C 4.1: pyridinium dichromate / CH₂Cl₂ / 40 °C 5.1: n-BuLi / tetrahydrofuran; hexane / 0.5 h / -78 °C 5.2: 67 percent / tetrahydrofuran; hexane / 1 h 6.1: SOCl₂ / CH₂Cl₂ / 1 h / 25 °C 7.1: 76 percent / acetonitrile / 12 h / 80 °C

Reference： [1]Plobeck; Delorme; Wei; Yang; Zhou; Schwarz; Gawell; Gagnon; Pelcman; Schmidt; Yue; Walpole; Brown; Zhou; Labare; Payza; St-Ogne; Kamassah; Morin; Projean; Ducharme; Roberts [Journal of Medicinal Chemistry, 2000, vol. 43, # 21, p. 3878 - 3894]

30
[ 1563-38-8 ]
[ 1563-66-2 ]

Yield	Reaction Conditions	Operation in experiment
	Multi-step reaction with 2 steps 1: 84 percent / pyridine / CH₂Cl₂ / 5 h / Ambient temperature 2: 79 percent / aq. K₂CO₃ / tetrahydrofuran / 20 °C
	Multi-step reaction with 2 steps 1: 73.5 percent / Adogen 464, NaOH / benzene; H₂O / 0.67 h / 5 °C 2: 75.1 percent / Et₃N / petroleum ether; H₂O / 2.08 h / Ambient temperature
	In <i>N</i>,<i>N</i>-dimethyl-aniline	23.c (b) (c) The procedure is as in (a) followed by (b), but pyridine is replaced by N,N-dimethylaniline and the intermediate carbonate is not distilled. Starting with 16.4 g of 2,3-dihydro-2,2-dimethyl-7-benzofuranol, 16.8 g (76%) of CARBOFURAN are then obtained, M.p. 147° C.

Reference： [1]Barcelo, Gerard; Senet, Jean-Pierre; Sennyey, Gerard; Bensoam, Jean; Loffet, Albert [Synthesis, 1986, # 8, p. 627 - 632]
[2]Patonay, Tamas; Patonay-Peli, Erzsebet; Mogyorodi, Ferenc [Synthetic Communications, 1990, vol. 20, # 18, p. 2865 - 2885]
[3]Current Patent Assignee: AURELIUS SE & CO KGAA - US4725680, 1988, A

31
[ 1563-38-8 ]
[ 530-62-1 ]
2,2-dimethyl-2,3-dihydrobenzo[2,3-b]benzofuran-7-yl imidazolecarboxylate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	In dichloromethane at 20℃; for 0.333333h;	4.o; 4.A Scheme 4; EXAMPLE 4; This example illustrates the preparation of N-{3-[4-(3,3-dichloroprop-2-enyloxy)-2,6-dichlorophenoxy]propyl}(2,2-dimethyl(2,3-dihydrobenzo[2,3-b]furan-7-yloxy))-carboxamide (Compound 53 in table below); Step A Synthesis of 2,2-dimethyl-2,3-dihydrobenzo[2,3-b]benzofuran-7-yl imidazolecarboxylate as an Intermediate A solution of 1.64 grams (0.010 mole) of 2,2-dimethyl-2,3-dihydrobenzo[b]furan-7-ol (known compound) in 30 mL of methylene chloride was stirred, and 1.62 grams (0.010 mole) of 1,1'-carbonyldiimidazole was added in one portion. Upon completion of addition the reaction mixture was stirred at ambient temperature for 20 minutes. After this time the reaction mixture was concentrated under reduced pressure to a residue. The residue was dissolved in a mixture of 1:1 methylene chloride and hexanes and purified by column chromatography on silica gel using a mixture of 7:4 hexane and ethyl acetate as an eluant. The appropriate fractions were combined and concentrated under reduced pressure, yielding 1.96 grams of the subject compound. The NMR spectrum was consistent with the proposed structure.

Reference： [1]Current Patent Assignee: FMC CORP - US2004/224994, 2004, A1 Location in patent: Page 8-9; 14

32
[ 1563-38-8 ]
[ 791063-97-3 ]
[ 791063-98-4 ]

Yield	Reaction Conditions	Operation in experiment
	With potassium carbonate In DMF (N,N-dimethyl-formamide) at 80℃; for 18h;	1.b; 1.B Scheme 1; Step B Synthesis of 2-[4-(2,2-dimethyl(2,3-dihydrobenzo[2,3-b]furan-7-yloxy))butoxy]-1,3-dichloro-5-(phenylmethoxy)benzene as an Intermediate A stirred solution of 1.0 gram (0.0028 mole) of 1,3-dichloro-2-(4-chlorobutoxy)-5-(phenylmethoxy)benzene, 0.6 gram (0.0034 mole) of 2,2-dimethyl-2,3-dihydrobenzo[b]furan-7-ol (known compound), and 0.6 gram (0.0043 mole) of potassium carbonate in 25 mL of DMF was heated at 80° C. for about 18 hours. After this time, the reaction mixture was cooled and 50 mL of water was added. The mixture was then extracted with three 25 mL portions of diethyl ether. The combined extracts were washed with 25 mL of an aqueous solution saturated with sodium chloride. The organic layer was dried with sodium sulfate, filtered, and concentrated under reduced pressure to a residue. The residue was purified with column chromatography on silica gel using mixtures of 1:3 methylene chloride:hexane and 1:1 methylene chloride:hexane as eluants. The appropriate fractions were combined and concentrated under reduced pressure, yielding 0.87 gram of the subject compound. The NMR spectrum was consistent with the proposed structure.

Reference： [1]Current Patent Assignee: FMC CORP - US2004/224994, 2004, A1 Location in patent: Page 6; 12

33
[ 5470-18-8 ]
[ 1563-38-8 ]
[ 790249-60-4 ]

Yield	Reaction Conditions	Operation in experiment
73%	With caesium carbonate In DMF (N,N-dimethyl-formamide) at 80℃; for 10h;	134a 134a 2- (2, 2-dimethyl-2, 3-dihydrobenzofuran-7-yloxy)-3-nitropyridine [00349] A solution of 2-chloro-3-nitropyridine (4.9 g, 30.9 mmol) in DMF (50 mL) was treated with 2,2-dimethyl-2, 3-dihydrobenzofuran-7-ol (5.3 mL, 46.4 mmol) and cesium carbonate (30. 2 g, 92.7 mmol). The mixture was heated at 80°C for 10 h. The reaction was cooled to rt, and the mixture was poured in water (200 mL) with stirring. The yellow precipitate formed was filtered and washed with water, and recrystallized from ethanol (50 mL) to afford 134a as brown crystals (6.5 g, 73% yield). [M+H] +-287. 16. 1H NMR (500 MHz, deuterochloroform) 8 ppm 8.38 (dd, lH, J=1. 7Hz, J=5. OHz), 8.31 (dd, lH, J = 5.0 Hz, J=l. 7Hz), 7.12 (dd, 1H, J = 10. 0 Hz, J=5. OHz), 7.05 (d, 1H, J=5. OHz), 7.00 (d, 1H, J = 10. 0 Hz), 6.86 (t, 1H, J = 10.0 Hz), 3.05 (s, 2H), 1.39 (s, 6H) ; 13C (125 MHz, deuterochloroform) 8 (ppm), 1. 55. 42, 1. 51-76, 150.16, 136. 03,135. 40,134. 04,129. 76, 122.60, 121. 06,120. 37,118. 07, 88.40, 43.07, 27.98.

Reference： [1]Current Patent Assignee: BRISTOL-MYERS SQUIBB CO - WO2005/70920, 2005, A1 Location in patent: Page/Page column 103-104

34
[ 1563-38-8 ]
[ 4753-59-7 ]
[ 884604-53-9 ]

Yield	Reaction Conditions	Operation in experiment
	With potassium carbonate In N,N-dimethyl-formamide at 20℃; for 120h;	2.A Under a nitrogen atmosphere a solution of 5.0 grams (0.030 mole) of 7- hydroxybenzofuran (known compound), 6.5 grams (0.033 mole) of 4-bromobutyl acetate and 6.2 grams (0.045 mole) of potassium carbonate in 75 mL of DMF was stirred at ambient temperature during a five-day period. The reaction mixture was then stirred with 75 mL of water and saturated with solid sodium chloride. The mixture was extracted with three 50 mL portions of diethyl ether, and the combined extracts were washed with one 50 mL portion of water. The organic layer was then dried with sodium sulfate, filtered, and the filtrate was concentrated under reduced pressure, yielding 8.0 grams of the subject compound. The NMR spectrum was consistent with the proposed structure.

Reference： [1]Current Patent Assignee: FMC CORP - WO2006/47438, 2006, A2 Location in patent: Page/Page column 25

35
[ 1563-38-8 ]
ammonium chloride [ No CAS ]
[ 308110-31-8 ]

Yield	Reaction Conditions	Operation in experiment
32 g (96%)	With pyridine; trifluoromethylsulfonic anhydride In dichloromethane	1.i (i) (i) Preparation of 2,2-Dimethyl-2,3-dihydro-1-benzofuran-7-yl Trifluoromethanesulfonate (Compound 1) 2,2-dimethyl-2,3-dihydro-1-benzofuran-7-ol (19 g, 0.11 mol) and pyridine (18 mL, 0.23 mol) was dissolved in CH2Cl2 at 0° C. Triflic anhydride (23 mL, 0.14 mol) was added dropwise. After strirring 1 h at 25° C. the mixture was diluted with CH2Cl2 and washed with HCl (aq.), dried (Mg SO4) and evaporated in vacuo. Yield 32 g (96%) of compound 1, which did not need purification but was used directly in the following step. 1H NMR (CDCl3) δ 1.50 (s, 6H), 3.09 (s, 2H), 6.81 (m, 1H), 7.03 (m, 1H), 7.11 (m, 1H), MS (EI) m/e 296, 163, 135, 107.

Reference： [1]Current Patent Assignee: ASTRAZENECA PLC - US2003/105110, 2003, A1

36
[ 75-21-8 ]
2-Chloro-3-(1-piperazinyl)pyrazine.* [ No CAS ]
[ 1563-38-8 ]
[ 110-16-7 ]
[ 108-88-3 ]
[ 85386-99-8 ]
2-(2,3-Dihydro-2,2-dimethyl-7-benzofuranyloxy)ethyl 3-(1-piperazinyl)-2-pyrazinyl Ether, Maleate [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
1.40 g (72%)	With triethylamine In 1,4-dioxane; methanol; potassium <i>tert</i>-butylate	158 2-(2,3-Dihydro-2,2-dimethyl-7-benzofuranyloxy)ethyl 3-(1-piperazinyl)-2-pyrazinyl Ether, Maleate Example 158 2-(2,3-Dihydro-2,2-dimethyl-7-benzofuranyloxy)ethyl 3-(1-piperazinyl)-2-pyrazinyl Ether, Maleate A mixture of 2,3-dihydro-2,2-dimethyl-7-benzofuranol (0.82 g, 5.0 mmol), ethylene oxide (0.22 g, 5.0 mmol), triethylamine (3 drops) and dioxane (4 mL) was heated at 100° C. in a sealed tube for 3 d. The solution was cooled in an ice-bath and KO-t-Bu (0.56 g, 5 mmol) followed by 2-chloro-3-(-1-piperazinyl)pyrazine (0.79 g, 4.0 mmol; from Example 90, Step 1) were added. The mixture was stirred at room temperature for 30 min and at 100° C. for 4 h, allowed to cool, diluted with CH2Cl2 and filtered. The filtrate was concentrated and purified by chromatography on silica gel (gradient: PhMe to PhMe/MeOH/Et3N, 8:1:1) to give 1.46 g of a beige viscous oil. Maleic acid (0.46 g, 4.0 mmol) and dry MeOH (10 mL) was added. The mixture was heated until a clear solution formed. Upon cooling, the maleate salt of the title compound crystallized as a pale beige solid: yield 1.40 g (72%); mp 156-157° C. Anal. (C20H26N4O3.C4H4O4) C, H, N.

Reference： [1]Current Patent Assignee: BENEVOLENTAI LIMITED - US6465467, 2002, B1

37
[ 1563-38-8 ]
[ 98-88-4 ]
[ 17781-16-7 ]

Yield	Reaction Conditions	Operation in experiment
	In pyridine; water; acetic acid	15 7-Hydroxy-2,2-dimethyl-benzofuran-3-one EXAMPLE 15 7-Hydroxy-2,2-dimethyl-benzofuran-3-one 7-Hydroxy-2,3-dihydro-2,2-dimethylbenzofurane is dissolved in 100 ml pyridine. 0.5 mol benzoyl chloride is added dropwise at 0° C. within 4 h. Subsequently it is stirred for 10 h at room temperature. It is poured onto 200 ml ice water and aspirated. The residue is washed with 500 ml 2 M hydrochloric acid and then with 1000 ml water and dried in air. A solution of 0.906 mol chromium trioxide in 370 ml glacial acetic acid is added dropwise to a solution of this crude product (0.45 mol) in 600 ml glacial acetic acid in such a way that the temperature of the mixture does not exceed 20° C. After the dropwise addition is completed it is stirred for a further 1 hour at 40° C. and subsequently poured onto 2 l water. It is suction filtered. The residue is washed with 1 l water and recrystallized from ethanol/water 3:1. The benzoyl compound is fed into 400 ml 10% ethanolic potassium hydroxide solution and the mixture is heated for 1 hour to 70° C. It is admixed with 3 l water and suction filtered. The residue is recrystallized from 2 l water. Yield 0.16 mol

Reference： [1]Current Patent Assignee: ROCHE HOLDING AG - US6107036, 2000, A

38
[ 1563-38-8 ]
[ 96-31-1 ]
[ 111-92-2 ]
[ 1563-66-2 ]

Yield	Reaction Conditions	Operation in experiment
52.5%	With hydrogenchloride; sodium hydroxide; Isopropylbenzene In water	15 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate EXAMPLE 15 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate To a 250 ml, 3-neck flask, equipped with an agitator, a condenser, and a sub-surface gas addition system were added 11.0 g (0.125 mol) of 1,3-dimethylurea, 16.2 g (0.125 mol) of dibutylamine, and 100 ml of cumene. The solution was heated until the solvent began to reflux (about 151° C.). Heating was continued for about 6 hours while the solvent was refluxed and the monomethylamine generated during the reaction was allowed to escape. When monomethylamine evolution appeared to cease, the solution was cooled to about 80° C. and 16.4 g (0.10 mol) of 2,3-dihydro-2,2-dimethylbenzofuran-7-ol were added. Anhydrous hydrochloric acid gas (4.6 g, 0.125 mol) was added sub-surface to the liquid at a rate such that the temperature of the contents of the flask remained about 80° C. The resulting solution was heated to about 115° C. and stirred at that temperature for 16 hours. After 16 hours the solution was heated to reflux (about 154° C.) and stirred at that temperature for one hour. The solution was then cooled to about 80° C. and 50 ml of deionized water were added. The pH of the resulting two-phase mixture was increased to about 4.0 using a few drops of a 50% sodium hydroxide solution. The two-phase mixture was then stirred for 30 minutes at about 80° C. and the organic layer was separated from the aqueous layer. The organic layer was mixed with 25 ml of deionized water and cooled to about 0° C. After stirring the two-phase mixture for 30 minutes at a temperature of about 0° C. the resulting slurry was filtered and the recovered crystals washed with 20 ml of deionized water. These crystals, dried in a vacuum oven at 60° C., provided 11.6 g (52.5% yield) of 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate. mp=151.0°-152.0° C.
52.5%	With hydrogenchloride; sodium hydroxide; Isopropylbenzene In water	15 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate Example 15 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate To a 250 ml, 3-neck flask, equipped with an agitator, a condenser, and a sub-surface gas addition system were added 11.0 g (0.125 mol) of 1,3-dimethylurea, 16.2 g (0.125 mol) of dibutylamine, and 100 ml of cumene. The solution was heated until the solvent began to reflux (about 151°C). Heating was continued for about 6 hours while the solvent was refluxed and the monomethylamine generated during the reaction was allowed to escape. When monomethylamine evolution appeared to cease, the solution was cooled to about 80°C and 16.4 g (0.10 mol) of 2,3-dihydro-2,2-dimethylbenzofuran-7-ol were added. Anhydrous hydrochloric acid gas (4.6 g, 0.125 mol) was added sub-surface to the liquid at a rate such that the temperature of the contents of the flask remained about 80°C. The resulting solution was heated to about 115°C and stirred at that temperature for 16 hours. After 16 hours the solution was heated to reflux (about 154°C) and stirred at that temperature for one hour. The solution was then cooled to about 80°C and 50 ml of deionized water were added. The pH of the resulting two-phase mixture was increased to about 4.0 using a few drops of a 50% sodium hydroxide solution. The two-phase mixture was then stirred for 30 minutes at about 80°C and the organic layer was separated from the aqueous layer. The organic layer was mixed with 25 ml of deionized water and cooled to about 0°C. After stirring the two-phase mixture for 30 minutes at a temperature of about 0°C the resulting slurry was filtered and the recovered crystals washed with 20 ml of deionized water. These crystals, dried in a vacuum oven at 60°C, provided 11.6 g (52.5% yield) of 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate. mp = 151.0°-152.0°C.

Reference： [1]Current Patent Assignee: ELI LILLY & CO - US4987233, 1991, A
[2]Current Patent Assignee: CORTEVA INC - EP296864, 1988, A2

39
[ 1563-38-8 ]
[ 142-84-7 ]
[ 1563-66-2 ]

Yield	Reaction Conditions	Operation in experiment
55.7%	With hydrogenchloride; Isopropylbenzene In water; methyl isocyanate	13 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate EXAMPLE 13 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate To a 250 ml, 3-neck flask, equipped with an agitator, a condenser, and a dropping funnel were added 100 ml of cumene and 11.1 g (0.11 mol) of dipropylamine. Methylisocyanate (7.5 g, 0.13 mol) was added at a rate such that the temperature of the contents of the flask remained below 60° C. Once methylisocyanate addition was complete, the resulting solution was heated to refux (about 150° C.) and a total of 10 ml of cumene were distilled in order to remove unreacted methylisocyanate. Following removal of the unreacted methylisocyanate and the 10 ml of cumene, the remaining solution was cooled to about 80° C. and 16.4 g (0.10 mol) of 2,3-dihydro-2,2-dimethylbenzofuran-7-ol were added. Anhydrous hydrochloric acid gas (4.0 g, 0.11 mol) was added sub-surface to the liquid. After hydrochloric acid addition, the resulting solution was heated to reflux (about 154° C.) and stirred at that temperature for about 4 hours. The solution was then cooled to about 90° C. and 50 ml of deionized water were added. The resulting two-phase mixture was stirred for 30 minutes at about 80° C. and the organic layer was separated from the aqueous layer. The organic layer was mixed with 25 ml of deionized water and cooled to about 0° C., then stirred at that temperature for 30 minutes. The resulting slurry was filtered and the recovered crystals washed with 25 ml of deionized water. The crystals were then dried in a vacuum oven at 60° C. to provide 12.3 g (55.7% yield) of 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate. mp=151.0°-152.0° C.
55.7%	With hydrogenchloride; Isopropylbenzene In water; methyl isocyanate	13 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate Example 13 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate To a 250 ml, 3-neck flask, equipped with an agitator, a condenser, and a dropping funnel were added 100 ml of cumene and 11.1 g (0.11 mol) of dipropylamine. Methylisocyanate (7.5 g, 0.13 mol) was added at a rate such that the temperature of the contents of the flask remained below 60°C. Once methylisocyanate addition was complete, the resulting solution was heated to refux (about 150°C) and a total of 10 ml of cumene were distilled in order to remove unreacted methylisocyanate. Following removal of the unreacted methylisocyanate and the 10 ml of cumene, the remaining solution was cooled to about 80°C and 16.4 g (0.10 mol) of 2,3-dihydro-2,2-dimethylbenzofuran-7-ol were added. Anhydrous hydrochloric acid gas (4.0 g, 0.11 mol) was added sub-surface to the liquid. After hydrochloric acid addition, the resulting solution was heated to reflux (about 154°C) and stirred at that temperature for about 4 hours. The solution was then cooled to about 90°C and 50 ml of deionized water were added. The resulting two-phase mixture was stirred for 30 minutes at about 80°C and the organic layer was separated from the aqueous layer. The organic layer was mixed with 25 ml of deionized water and cooled to about 0°C, then stirred at that temperature for 30 minutes. The resulting slurry was filtered and the recovered crystals washed with 25 ml of deionized water. The crystals were then dried in a vacuum oven at 60°C to provide 12.3 g (55.7% yield) of 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate. mp = 151.0°-152.0°C.

Reference： [1]Current Patent Assignee: ELI LILLY & CO - US4987233, 1991, A
[2]Current Patent Assignee: CORTEVA INC - EP296864, 1988, A2

40
[ 1563-38-8 ]
[ 36614-21-8 ]
[ 1563-66-2 ]

Yield	Reaction Conditions	Operation in experiment
60.6%	With hydrogenchloride; sodium hydroxide; Isopropylbenzene In water	14 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate EXAMPLE 14 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate To a 250 ml, 3-neck flask, equipped with an agitator, a condenser, and a sub-surface gas addition system were added 16.4 g (0.10 mol) of 2,3-dihydro-2,2-dimethylbenzofuran-7-ol, 20.7 g (0.13 mol) of 1,1-dipropyl-3-methylurea (prepared according to the procedure of Preparation 2), and 100 ml of cumene. Anhydrous hydrochloric acid gas (4.6 g, 0.125 mol) was added subsurface to the liquid. The resulting solution was heated to about 115° C. and stirred at that temperature for about 16 hours. After 16 hours the solution was heated to reflux (about 155° C.) and stirred at that temperature for one hour. The solution was then cooled to about 80° C. and 50 ml of deionized water were added. The pH of the resulting two-phase mixture was increased to about 4.0 using a few drops of a 50% sodium hydroxide solution. After the pH was increased, the two-phase mixture was stirred for 30 minutes at about 80° C. and the organic layer was separated from the aqueous layer. The organic layer was mixed with 25 ml of deionized water and cooled to about 0° C. After stirring the two-phase mixture for 30 minutes at a temperature of about 0° C. the resulting slurry was filtered and the recovered crystals washed with 20 ml of deionized water. These crystals, dried in a vacuum oven at 60° C., provided 13.4 g (60.6% yield) of 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate. m.p.=151.0°-152.0° C.
60.6%	With hydrogenchloride; sodium hydroxide; Isopropylbenzene In water	14 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate Example 14 2,3-Dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate To a 250 ml, 3-neck flask, equipped with an agitator, a condenser, and a sub-surface gas addition system were added 16.4 g (0.10 mol) of 2,3-dihydro-2,2-dimethylbenzofuran-7-ol, 20.7 g (0.13 mol) of 1,1-dipropyl-3-methylurea (prepared according to the procedure of Preparation 2), and 100 ml of cumene. Anhydrous hydrochloric acid gas (4.6 g, 0.125 mol) was added sub-surface to the liquid. The resulting solution was heated to about 115°C and stirred at that temperature for about 16 hours. After 16 hours the solution was heated to relux (about 155°C) and stirred at that temperature for one hour. The solution was then cooled to about 80°C and 50 ml of deionized water were added. The pH of the resulting two-phase mixture was increased to about 4.0 using a few drops of a 50% sodium hydroxide solution. After the pH was increased, the two-phase mixture was stirred for 30 minutes at about 80°C and the organic layer was separated from the aqueous layer. The organic layer was mixed with 25 ml of deionized water and cooled to about 0°C. After stirring the two-phase mixture for 30 minutes at a temperature of about 0°C the resulting slurry was filtered and the recovered crystals washed with 20 ml of deionized water. These crystals, dried in a vacuum oven at 60°C, provided 13.4 g (60.6% yield) of 2,3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate. m.p. = 151.0°-152.0°C.

Reference： [1]Current Patent Assignee: ELI LILLY & CO - US4987233, 1991, A
[2]Current Patent Assignee: CORTEVA INC - EP296864, 1988, A2

41
[ 107189-19-5 ]
[ 1563-38-8 ]

Yield	Reaction Conditions	Operation in experiment
	With pyridine hydrochloride	5 Preparation of 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran (solventless) EXAMPLE 5 Preparation of 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran (solventless) 2-(2-Hydroxy-2-methylpropoxy)phenol (2.47 g, 0.0136 mole) and solid pyridine hydrochloride (8.0 g, 0.069 mole) were combined and heated to reflux (222° C.) for one hour. After cooling, the mixture was diluted with water and extracted three times with 50 ml of dichloromethane. The combined dichloromethane layers were concentrated to give 0.81 g of a dark oil. 1 Hnmr analysis showed the presence of 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran, pyridine and 2-(2-Hydroxy-2-methylpropoxy)phenol.
	In toluene	6 Preparation of 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran in toluene EXAMPLE 6 Preparation of 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran in toluene 2-(2-hydroxy-2-methylpropoxy)phenol (0.2 g, 1.1 mmole), a catalytic amount of para-toluenesulfonic acid and 10 ml of toluene were combined in a single-necked 50 ml round bottom flask equipped with a magnetic stirrer, reflux condenser, Dean-Stark trap and heating mantle. The mixture was heated to reflux (111° C.) with stirring. Water appeared in the Dean-Stark trap almost immediately. The mixture was cooled and analyzed by GLC. The analysis confirmed the presence of 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran.

Reference： [1]Current Patent Assignee: SANOFI - US4639536, 1987, A
[2]Current Patent Assignee: SANOFI - US4639536, 1987, A

42
[ 1563-38-8 ]
[ 20098-48-0 ]
3,5-dichloro-4-(2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)-1-nitrobenzene [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	With potassium carbonate; In hexane; ethyl acetate; butanone;	Part A: Preparation of 3,5-Dichloro-4-(2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)-1-nitrobenzene To a solution containing 32.83 g of <strong>[20098-48-0]1,2,3-trichloro-5-nitrobenzene</strong> and 26.11 g of 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran in 300 ml of methyl ethyl ketone under an atmosphere of nitrogen and at room temperature was added 21.98 g of anhydrous potassium carbonate. The reaction mixture was heated to reflux. Reflux was maintained for 30 hrs. The reaction mixture was cooled to room temperature and the solvents removed. The tan solid residue was dissolved in hot hexane containing a little ethyl acetate. This was filtered and the filtrate allowed to cool to room temperature then placed in freezer to cool further to promote crystallization. The crystals were collected and placed in a vacuum dessicator for drying. A second crop of crystals was obtained from the mother liquors. This afforded 29.2 g of pale tan crystals. mp 105-110 C. NMR (CDCl3): 1.47 (s, 6H), 3.03 (s, 2H), 6.3-7.0 (m, 3H), 8.22 (s, 2H).

Reference： [1]Patent: US4665097,1987,A

43
[ 1563-38-8 ]
[ 99-54-7 ]
3-chloro-4-(2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)-1-nitrobenzene [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	With potassium carbonate In water; ethyl acetate; N,N-dimethyl-formamide	162.A Part A: Part A: Preparation of 3-Chloro-4-(2,3-dihydro-2,2-dimethyl-7-benzofuranyloxy)-1-nitrobenzene To a mixture containing 32.63 g (0.236 mole) of anhydrous potassium carbonate and 30.41 g (0.158 mole) of 3,4-dichloro-1-nitrobenzene in 250 ml of dry DMF at room temperature and under an atmosphere of nitrogen was added 30.88 g (0.188 mole) of 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran. The reaction mixture was then placed in an oil bath and heated to 110° C. for 20 hours The reaction mixture was cooled to room temperature. The DMF was removed under vacuum. The residue was dissolved in 1.5 L of 1:1 ethylacetate:ether and 300 ml of water. The layers were separated. The organic layer was washed twice with 5% NaOH, twice with H2 O and once with a saturated aqueous NaCl solution. After drying over anhydrous Na2 SO4, removal of the solvents afforded 48.42 g of a light tan solid. This was recrystallized from hexane:ethyl acetate to afford 44.19 g of white crystals mp 132°-133° C. NMR (CDCl3): δ1.42 (s, 6H), 3.05 (s, 2H), 6.5-7.2 (m, 4H), 7.95 (doft, J=9, 2 Hz, 1H), 8.28 (d, J=2 Hz, 1H).

Reference： [1]Current Patent Assignee: SANOFI; DOW INC - US4426385, 1984, A

44
[ 63942-40-5 ]
[ 1563-38-8 ]
2,2-Dimethyl-2,3-dihydro-7-[N-methyl-N-(N'-methyl-N'-fluorocarbonyl-aminosulfenyl)-carbamoyloxy]benzofuran [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
	With triethylamine In 1,4-dioxane; ethyl acetate	VI Preparation of 2,3-Dihydro-2,2-dimethyl-7-[N-methyl-N-(N'-methyl-N'-fluorocarbonylaminosulfenyl) carbamoyloxy]benzofuran EXAMPLE VI Preparation of 2,3-Dihydro-2,2-dimethyl-7-[N-methyl-N-(N'-methyl-N'-fluorocarbonylaminosulfenyl) carbamoyloxy]benzofuran To a solution of 5.0 g bis-(N-methyl-N-fluorocarbonyl)amino sulfide and 5.0 g of 2,2-dimethyl-2,3-dihydrobenzofuran-7-ol in 75 ml dioxane was added 4.0 g of triethylamine. After allowing the reaction mixture to stand at ambient temperature for 6 days, it was diluted with 200 ml water and extracted in ethyl acetate. The ethyl acetate extract was washed with water, dried and concentrated under vacuo. Purification by silica gel chromatography yielded 5.0 g of product as a viscous oil. Calcd. for C14 H17 FN2 O4 S: C, 51.21; H, 5.21; N, 8.53. Found: C, 51.90; H, 5.34; N, 8.60.
	With triethylamine In 1,4-dioxane; ethyl acetate	III Preparation of 2,3-Dihydro-2,2-dimethyl-7-[N-methyl-N-(N'-methyl-N'-fluorocarbonylaminosulfenyl)carbamoyloxy]benzofuran EXAMPLE III Preparation of 2,3-Dihydro-2,2-dimethyl-7-[N-methyl-N-(N'-methyl-N'-fluorocarbonylaminosulfenyl)carbamoyloxy]benzofuran To a solution of 5.0 g of N,N'-bis-(N-methyl-N-fluorocarbonylamino) sulfide and 5.0 g of 2,3-dihydro-2,2-dimethylbenzofuran-7-ol in 75 ml of dioxane was added 4.0 g of triethylamine. After allowing the reaction mixture to stand at ambient temperature for 6 days, it was diluted with 200 ml of water and was extracted in ethyl acetate. The organic extract was washed with water, dried over magnesium sulfate and concentrated. Purification by chromatography using silica gel afforded 5.0 g of the product as a viscous oil. Calc'd for C14 H17 FN2 O4 S: C, 51.21; H, 5.21; N, 8.53. Found: C, 51.90; H, 5.34; N, 8.60.
	With triethylamine In 1,4-dioxane; water; ethyl acetate	II Preparation of 2,2-Dimethyl-2,3-dihydro-7-[N-methyl-N-(N'-methyl-N'-fluorocarbonylaminosulfenyl)carbamoyloxy]benzofuran EXAMPLE II Preparation of 2,2-Dimethyl-2,3-dihydro-7-[N-methyl-N-(N'-methyl-N'-fluorocarbonylaminosulfenyl)carbamoyloxy]benzofuran To a solution of 5.0 g of bis-(N-methyl-N-fluorocarbonylamino) sulfide, prepared as Example I, and 5.0 g of 2,2-dimethyl-2,3-dihydrobenzofuran-7-ol in 75 ml of dioxane, was added 4.0 g of triethylamine. After allowing the reaction mixture to stand at ambient temperature for 6 days, it was diluted with 200 ml of water and extracted in ethyl acetate. The ethyl acetate extract was washed with water, dried and concentrated under vacuo. Purification by silica gel chromatography afforded 5.0 g of 2,2-Dimethyl-2,3-dihydro-7-[N-methyl-N-(N'-methyl-N'-fluorocarbonylaminosulfenyl)carbamoyloxy]benzofuran as a viscous oil. Calc'd for C14 H17 FN2 O4 S: C, 51.21; H, 5.21; N, 8.53. Found: C, 51.90; H, 5.34; N, 8.60.

With triethylamine In 1,4-dioxane; water; ethyl acetate

II Preparation of 2,2-Dimethyl-2,3-dihydro-7-[N-methyl-N(N-'-methyl-N'-fluorocarbonylaminosulfenyl) carbamoyloxy] benzofuran EXAMPLE II Preparation of 2,2-Dimethyl-2,3-dihydro-7-[N-methyl-N(N-'-methyl-N'-fluorocarbonylaminosulfenyl) carbamoyloxy] benzofuran To a solution of 5.0 g of bis-(N-methyl-N-fluorocarbonylamino) sulfide, prepared as Example I, and 5.0 g of 2,2-dimethyl-2,3-dihydrobenzofuran-7-ol in 75 ml of dioxane, was added 4.0 g of triethylamine. After allowing the reaction mixture to stand at ambient temperature for 6 days, it was diluted with 200 ml of water and extracted in ethyl acetate. The ethyl acetate extract was washed with water, dried and concentrated under vacuo. Purification by silica gel chromatography afforded 5.0 g of 2,2-Dimethyl-2,3-dihydro-7-[N-methyl-N-(N'-methyl-N'-fluorocarbonyl-aminosulfenyl) carbamoyloxy]benzofuran as a viscous oil. Calc'd for C14 H17 FN2 O4 S: C, 51.21; H, 5.21; N, 8.53 Found: C, 51.90; H, 5.34; N, 8.60

Reference： [1]Current Patent Assignee: SANOFI - US4338450, 1982, A
[2]Current Patent Assignee: SANOFI - US4400389, 1983, A
[3]Current Patent Assignee: SANOFI - US4181734, 1980, A
[4]Current Patent Assignee: SANOFI - US4124721, 1978, A

45
N-methylcarbamoyl-benzoic acid sulfimide [ No CAS ]
[ 1563-38-8 ]
[ 1563-66-2 ]

Yield	Reaction Conditions	Operation in experiment
	With triethylamine In water; acetone	3 EXAMPLE 3 EXAMPLE 3 1.5 g of N-methylcarbamoyl-benzoic acid sulfimide are suspended in a mixture of 1 g of 2,3-dihydro-2,2-dimethylbenzofurane-7-ol in 5 ml of acetone and 5 ml of water, where upon a solution of 0.6 g of triethyl amine in a mixture of 2 ml of acetone and 1 ml of water is added dropwise in 30 minutes, and the mixture is stirred for an additional 1.5 hours. The precipitated crystals are filtered off, washed with water and dried. 0.745 g of 2,3-dihydro-2,2-dimethylbenzofurane-7-yl methylcarbamate are obtained, melting at 150° to 152° C.

Reference： [1]Current Patent Assignee: SANOFI - US4315861, 1982, A

46
N-methylcarbamoyl-benzoic acid sulfimide [ No CAS ]
[ 1563-38-8 ]
benzoic acid sulfimide [ No CAS ]
[ 1563-66-2 ]

Yield	Reaction Conditions	Operation in experiment
	In water; triethylamine; acetone	2 EXAMPLE 2 EXAMPLE 2 3.35 g (0.025 moles) of 2,3-dihydro-2,2-dimethyl-benzofuran-7-ol are reacted with 6 g (0.025 moles) of N-methylcarbamoyl-benzoic acid sulfimide in 15 ml of acetone, in the presence of 2.56 g (0.025 moles) of triethyl amine, at 50° C. for 15 minutes. The reaction mixture is then cooled to room temperature, diluted with 100 ml of water; the precipitate is filtered off, washed with water and dried. 3.1 g of 2,3-dihydro-2,2-dimethyl-benzofurane-7-yl methyl-carbamate are obtained, melting at 150° to 152° C. Benzoic acid sulfimide can be recovered by precipitation from the mother liquor with an acid.

Reference： [1]Current Patent Assignee: SANOFI - US4315861, 1982, A

47
(2-fluorocarbonyl-4-cyano-4-methyl)-2-aza-3-sulfa-pentane [ No CAS ]
[ 1563-38-8 ]
[ 78744-19-1 ]

Yield	Reaction Conditions	Operation in experiment
	With triethylamine In diethyl ether; water; toluene	1.b (b) (b) Production of N-(2-isobutyronitrilesulfenyl)-(2,3-dihydro-2,2-dimethyl-7-benzofuranyl)-N-methyl carbamate (final product) To a solution of 5.5 g of 2,3-dihydro-2,2-dimethyl-7-hydroxybenzofuran in 80 ml of toluene were added, with stirring, 5.95 ml of triethylamine, and there were subsequently added dropwise, at a maximum of 30° C., 5.9 g of (2-fluorocarbonyl-4-cyano-4-methyl)-2-aza-3-sulfa-pentane. The reaction mixture was then stirred for 16 hours at room temperature and for 21/2 hours at 40°-50° C., filtered, and concentrated by evaporation. The crude product was taken up in diethyl ether and washed four times with 50 ml of water each time; the organic phase was then dried over Na2 SO4 and finally concentrated by evaporation. By this procedure is obtained N-(2-isobutyronitrilesulfenyl)-(2,3-dihydro-2,2-dimethyl-7-benzofuranyl)-N-methyl carbamate of the formula STR11 in the form of a yellow oil having a refractive index of nD21 °: 1.5293.

Reference： [1]Current Patent Assignee: NOVARTIS AG; Novartis (w/o Sandoz) - US4305957, 1981, A

48
[ 104-15-4 ]
[ 53889-58-0 ]
[ 1563-38-8 ]

Yield	Reaction Conditions	Operation in experiment
67%	With sodium hydroxide In benzene	6 Preparation of 2,2-dimethyl-2,3-dihydro-7-hydroxybenzofuran by the dihydrohalogenation, hydrolysis and cyclization of 2,2-dichloro-6-chloro-6-(1-chloroisobutyl)cyclohexanone The reaction solution was neutralized with hydrochloric acid and extracted with benzene. After distilling the benzene off, 30 mg of paratoluene sulfonic acid was added to the residue and the mixture was heated and stirred at 120° C. for 1 hour. The reaction solution was dissolved in 5 ml of benzene and extracted with 5 ml of an aqueous solution containing 10% by weight of sodium hydroxide. The aqueous layer was made acidic with hydrochloric acid and then extracted with benzene, whereupon 0.6 g (67% yield based on 2-isobutenyl-6-chlorophenol) of 2,2-dimethyl-2,3-dihydro-7-hydroxybenzofuran was obtained.

Reference： [1]Current Patent Assignee: MITSUBISHI CHEMICAL HOLDINGS CORPORATION; Mitsubishi Chemical Corp (in: MCHC Group) - US4499306, 1985, A

49
85%-phosphoric acid (H3 PO4) [ No CAS ]
[ 120-80-9 ]
[ 78-84-2 ]
[ 1563-38-8 ]

Yield	Reaction Conditions	Operation in experiment
	With zinc diacetate In water; toluene	8 Example 8 Example 8 A 250-ml flask, equipped with a stirrer and a refluxing system with azeotropic removal of water (Marcusson) is charged with 110 g (1 mol) of catechol, 50 mls (39.6 g=0.55 mol) of isobutyraldehyde, 2.74 g (0.015 mol) of zinc acetate and 30 mls of toluene. The mixture is brought to a boil (about 120° C.) during about 7 hours, during which about 10 mls of water are withdrawn. From the reaction mixture there are now separated by distillation toluene and the unreacted isobutyraldehyde, working under a pressure of 30 mmHg. The residue of the distillation is supplemented with 7.0 g of 85%-phosphoric acid (H3 PO4), whereafter the temperature is raised to 245° C. and the pressure is stabilized at 20 mmHg. During a period of about 4 hours, there are evaporated and recovered 72.5 g (0.66 mol) of catechol and 21 g (0.13 mol) of 2,3-dihydro-2,2-dimethyl-7-benzofuranol.
	In water; toluene	9 Example 9 Example 9 A 250-ml flask, equipped with a stirrer and a refluxing system with azeotropic water elimination is charged with 165 g (1.5 mol) of catechol, 85 mls (67.32 g=0.93 mol) of isobutyraldehyde, 1 g (0.018 mol) of calcium oxide (CaO) and 40 mls of toluene. The mixture is brought to a boil (about 120° C.) for about 8 hours, in the course of which about 14 mls of water are removed. From the reaction mixture there are distilled off, then, toluene and the unreacted isobutyraldehyde, working under an absolute pressure of 30 mmHg. The distillation residue is supplemented with 9.4 g of 85%-phosphoric acid (H3 PO4), whereafter the temperature is raised to 245° C., and pressure stabilized at 20 mmHg. During a time of about 4 hours, there are evaporated and recovered 92 g (0.84 mol) of catechol and 50 g (0.31 mol) of 2,3-dihydro-2,2-dimethyl-7-benzofuranol.

Reference： [1]Current Patent Assignee: ENI SPA - US4562266, 1985, A
[2]Current Patent Assignee: ENI SPA - US4562266, 1985, A

50
[ 120-80-9 ]
[ 77-78-1 ]
[ 563-47-3 ]
[ 1563-38-8 ]

Yield	Reaction Conditions	Operation in experiment
	With sodium hydroxide In water	1 N,N-Dimethyl-2,3-dihydro-2,2-dimethyl-7-hydroxy-6-benzofuransulfonamide EXAMPLE 1 N,N-Dimethyl-2,3-dihydro-2,2-dimethyl-7-hydroxy-6-benzofuransulfonamide The starting material 2,3-dihydro-2,2-dimethyl-7-benzofuranol is prepared from catechol and 3-chloro-2-methylpropene as described by Neth. No. 6,500,340. The material (16.4 g) is added to 125 ml of water and contacted with 8 ml of 50% NaOH. After stirring one-half hour, 16.4 g of dimethylsulfate is added and the resulting suspension is stirred and heated at 60° for 2 hours. The resulting mixture is extracted with methylene chloride.

Reference： [1]Current Patent Assignee: DUPONT DE NEMOURS INC - US4494979, 1985, A

51
[ 1563-38-8 ]
2,3-dihydro-2,2-dimethyl-5-methylthio-7-benzofuranol [ No CAS ]
[ 96408-53-6 ]

Yield	Reaction Conditions	Operation in experiment
	With pyridine; perchloric acid; dimethyl sulfoxide; trichlorophosphate	7 O-Ethyl-O-(2,3-dihydro-2,2-dimethyl-5-methylthio-7-benzofuranyl)-ethylthionophosphonate EXAMPLE 7 O-Ethyl-O-(2,3-dihydro-2,2-dimethyl-5-methylthio-7-benzofuranyl)-ethylthionophosphonate To a mixture of 2,3-dihydro-2,2-dimethyl-7-benzofuranol (16.4 g), 20 ml of 70% perchloric acid and 16 ml of phosphorus oxychloride, dimethyl sulfoxide (7.8 g, 0.1 mol) was gradually added at a temperature of not higher than 5° C. The reaction solution was stirred at room temperature for further one hour, then poured into ice water and extracted with ethyl acetate. The ethyl acetate layer was washed with water, concentrated and then heated and refluxed, together with 200 ml of pyridine, for 4 hours. Pyridine was concentrated under reduced pressure, and the residue was washed with ether. The ether layer was washed with 1N hydrocloric acid and water successibly, then dried over anhydrous sodium sulfate and concentrated. The solid substance thereby obtained was recrystallized from ether-hexane, whereby 9.7 g of 2,3-dihydro-2,2-dimethyl-5-methylthio-7-benzofuranol was obtained. The melting of this product was 57°-59° C. The structure was confirmed by 1 H-NMR spectrum and IR spectrum.