Isosorbide,Methyl etherate and acid catalystAmberlyst-35 was put into a stainless steel reaction kettle,Closed reactor,130 ° C magnetic stirring for 15 hours. among them,The molar ratio of methylating reagent and isosorbide was 50: 1,The mass ratio of catalyst Amberlyst-35 to isosorbide was 0.5: 1. After the reactor was cooled to room temperature,The reaction solution was analyzed by gas chromatography. The conversion of isosorbide and its methylated product yield were calculated by gas chromatography internal standard method,In mole percent.
Reference:
[1] Patent: CN105646514, 2016, A, . Location in patent: Paragraph 0029; 0030; 0031; 0032; 0033; 0034
2
[ 150-78-7 ]
[ 39581-55-0 ]
Reference:
[1] Patent: CN107365322, 2017, A,
3
[ 107-20-0 ]
[ 504-02-9 ]
[ 150-78-7 ]
[ 16806-93-2 ]
Reference:
[1] Patent: EP101004, 1991, B2,
4
[ 68-12-2 ]
[ 150-78-7 ]
[ 7310-97-6 ]
Yield
Reaction Conditions
Operation in experiment
62%
Stage #1: With n-butyllithium; N,N,N,N,-tetramethylethylenediamine In diethyl ether; hexane at 0℃; for 5.5 h; Inert atmosphere; Reflux Stage #2: at -78℃; for 1 h; Inert atmosphere
A three-necked reactor equipped with a thermometer was charged with 7.0 g (50.67 mmol) of 1,4-dimethoxybenzene, 29.44 g (253.33 mmol) of N,N,N′,N′-tetramethylethylenediamine, and 280 ml of diethyl ether under a nitrogen stream to prepare a homogeneous solution. After cooling the solution to 0° C., 97.4 ml (253.33 mmol) of 2.6 M n-butyllithium (n-hexane solution) was added dropwise to the solution over 30 minutes. After the dropwise addition, the reaction mixture was reacted for 5 hours under reflux, and then cooled to −78° C. After the addition of 18.52 g (253.33 mmol) of N,N-dimethylformamide, the mixture was stirred at −78° C. for 1 hour. After the addition of 350 ml of a 3 N hydrochloric acid aqueous solution to the reaction mixture at −78° C., the mixture was heated to 25° C., and 300 ml of distilled water and 200 ml of a saturated sodium chloride solution were added to the mixture, followed by extraction with 700 ml of chloroform. The chloroform layer was dried over anhydrous sodium sulfate, and sodium sulfate was filtered off. The solvent was evaporated from the filtrate under reduced pressure using a rotary evaporator. The resulting solid was added to 100 ml of toluene. After stirring the mixture for 5 minutes, the resulting crystals were filtered off to obtain 6.1 g of an intermediate A as yellow crystals (yield: 62percent). (0225) The structure of the target product was identified by 1H-NMR. (0226) 1H-NMR (500 MHz, CDCl3, TMS, δ ppm): 10.51 (s, 2H), 7.46 (s, 2H), 3.95 (s, 6H).
Reference:
[1] Organic and Biomolecular Chemistry, 2003, vol. 1, # 7, p. 1157 - 1170
[2] Tetrahedron Letters, 2013, vol. 54, # 26, p. 3419 - 3423
[3] Patent: US2015/274647, 2015, A1, . Location in patent: Paragraph 0223-0226
[4] Organometallics, 2012, vol. 31, # 9, p. 3636 - 3646
[5] New Journal of Chemistry, 2016, vol. 40, # 7, p. 5877 - 5884
[6] Patent: CN107382905, 2017, A, . Location in patent: Paragraph 0008; 0081; 0087; 0088
5
[ 2591-86-8 ]
[ 150-78-7 ]
[ 7310-97-6 ]
Yield
Reaction Conditions
Operation in experiment
51%
Stage #1: With n-butyllithium; N,N,N,N,-tetramethylethylenediamine In hexane; ethyl acetate at 0℃; Inert atmosphere; Reflux Stage #2: at 0 - 20℃; for 1 h;
To a solution of 1-1 1 ,4-dimethoxybenzene (11.5 g, 83.26 mmol, 1 eq) in distilled Et20(276 mL) was added TMEDA (37,4 mL, 249.78 mmol, 3 eq). At 000, nBuLi at 2.5 M inhexane (100 mL, 249.78 mmol, 3 eq) was added dropwise. The mixture was stirred atreflux overnight under inert atmosphere. At 000, 1-formylpiperidine (27.74 mL, 249.78mmol, 3 eq). was added dropwise. The mixture was stirred at room temperature for 1 h.Following the addition of distilled water (300 mL) and HCI 3 M (57.5 mL), the mixture was extracted with hot CHCI3 (300 mLx4). The organic phase was dried over an hydrous Na2SO4 and filtered. After removing the solvent, the remaining residue was purified by recrystallization in CHCI3 to give an orange solid (9.51 g, 51 percent).1H NMR (300 MHz, ODd3) 6 ppm = 10.51 (s, 2 H, CHO), 7.46 (s, 2 H, Ar), 3.95 (s, 6 H,OH3) data matched with literature reference
Reference:
[1] Journal of the American Chemical Society, 2003, vol. 125, # 37, p. 11241 - 11248
[2] European Journal of Organic Chemistry, 1998, # 4, p. 595 - 604
[3] Journal of Medicinal Chemistry, 1984, vol. 27, # 8, p. 1071 - 1077
[4] Tetrahedron, 1983, vol. 39, # 5, p. 781 - 792
[5] Bulletin of the Korean Chemical Society, 2010, vol. 31, # 10, p. 2755 - 2756
[6] New Journal of Chemistry, 2014, vol. 38, # 7, p. 3042 - 3049
[7] Journal of Molecular Structure, 2016, vol. 1106, p. 121 - 129
[8] Patent: WO2015/163817, 2015, A1,
[9] Tetrahedron, 2017, vol. 73, # 20, p. 2886 - 2893
[10] Journal of Materials Chemistry A, 2018, vol. 6, # 2, p. 374 - 382
[11] Journal of the American Chemical Society, 2018, vol. 140, # 3, p. 984 - 992
[12] Journal of Photochemistry and Photobiology A: Chemistry, 2017, vol. 346, p. 194 - 205
[13] Journal of Photochemistry and Photobiology A: Chemistry, 2018, vol. 364, p. 705 - 714
[14] Angewandte Chemie - International Edition, 2018, vol. 57, # 35, p. 11310 - 11315[15] Angew. Chem., 2018, vol. 130, p. 11480 - 11485,6
7
[ 150-78-7 ]
[ 68602-57-3 ]
[ 34065-73-1 ]
[ 333-27-7 ]
Reference:
[1] Journal of Organic Chemistry, 1987, vol. 52, # 19, p. 4156 - 4159
8
[ 150-78-7 ]
[ 68602-57-3 ]
[ 34065-73-1 ]
[ 5672-87-7 ]
[ 333-27-7 ]
Reference:
[1] Journal of Organic Chemistry, 1987, vol. 52, # 19, p. 4156 - 4159
9
[ 75-36-5 ]
[ 150-78-7 ]
[ 705-15-7 ]
Reference:
[1] Gazzetta Chimica Italiana, 1948, vol. 78, p. 16,19
[2] Journal of the American Chemical Society, 1948, vol. 70, p. 1084,1086
[3] Journal of the Chemical Society, 1939, p. 1922,1926
[4] Journal of Medicinal Chemistry, 1975, vol. 18, # 12, p. 1201 - 1204
10
[ 64-19-7 ]
[ 150-78-7 ]
[ 705-15-7 ]
Reference:
[1] Archiv der Pharmazie (Weinheim, Germany), 1955, vol. 288, p. 102,107,108
11
[ 64-19-7 ]
[ 150-78-7 ]
[ 705-15-7 ]
[ 1201-38-3 ]
Reference:
[1] Archiv der Pharmazie (Weinheim, Germany), 1955, vol. 288, p. 102,107,108
12
[ 7446-70-0 ]
[ 60-29-7 ]
[ 75-36-5 ]
[ 150-78-7 ]
[ 705-15-7 ]
[ 1201-38-3 ]
Reference:
[1] Gazzetta Chimica Italiana, 1948, vol. 78, p. 16,19
[2] Journal of the Chemical Society, 1939, p. 1922,1926
13
[ 150-78-7 ]
[ 17332-11-5 ]
[ 583-69-7 ]
Reference:
[1] Journal of Organic Chemistry USSR (English Translation), 1983, p. 997 - 998[2] Zhurnal Organicheskoi Khimii, 1983, vol. 19, # 5, p. 1115 - 1116
14
[ 150-78-7 ]
[ 615-93-0 ]
Reference:
[1] Synthetic Communications, 2002, vol. 32, # 20, p. 3233 - 3239
[2] Bollettino Scientifico della Facolta di Chimica Industriale di Bologna, 1944, vol. 5, p. 38,40
15
[ 150-78-7 ]
[ 18113-03-6 ]
[ 18093-12-4 ]
[ 615-67-8 ]
Reference:
[1] Journal of Organic Chemistry USSR (English Translation), 1983, p. 997 - 998[2] Zhurnal Organicheskoi Khimii, 1983, vol. 19, # 5, p. 1115 - 1116
[3] Journal of Organic Chemistry USSR (English Translation), 1983, p. 997 - 998[4] Zhurnal Organicheskoi Khimii, 1983, vol. 19, # 5, p. 1115 - 1116
16
[ 150-78-7 ]
[ 18113-03-6 ]
[ 18093-12-4 ]
[ 615-67-8 ]
Reference:
[1] Journal of Organic Chemistry USSR (English Translation), 1983, p. 997 - 998[2] Zhurnal Organicheskoi Khimii, 1983, vol. 19, # 5, p. 1115 - 1116
[3] Journal of Organic Chemistry USSR (English Translation), 1983, p. 997 - 998[4] Zhurnal Organicheskoi Khimii, 1983, vol. 19, # 5, p. 1115 - 1116
17
[ 150-78-7 ]
[ 2674-34-2 ]
Yield
Reaction Conditions
Operation in experiment
85%
With bromine In chloroform at 0℃; for 3 h;
Example 2: Preparation of 2,5-dibromo-1 ,4-dimethoxybenzene (2); [00103] In a one liter round-bottom flask, a solution of bromine (35.2 g, 220 mmol) in chloroform (50 ml) was added dropwise to a solution of 1 ,4- dimethoxybenzene (13.8 g, 100 mmol) in chloroform (400 ml) under 00C. After stirring for 3 hours, 100 ml of saturated Na2CO3 solution was added. The organic layer was washed with water, brine, and dried over sodium sulfate. The solvent was removed on a rotary evaporator and the residue was performed recrystallization from ethanol to afford pure 2,5-dibromo-1 ,4- dimethoxybenzene (25.8 g, 85percent). 1HNMR (CDCI3) 57.128 (s, 2 H), 3.873 (s, 6 H).
83.6%
at 20℃; for 4 h; Sonication
In a 250 ml reaction flask, 20.0 g (0.145 mol, 1.0 eq) of hydroquinone dimethyl ether and 55 ml of glacial acetic acid were added and dissolved by ultrasonic; A solution of 15 ml of Br2 (0.290 mol, 2.0 eq) and 15 ml of glacial acetic acid was added dropwise at room temperature. After 1.5 hours, the mixture was stirred at room temperature for 2.5 h. Placed in the upper refrigerator to 10 below the temperature (not to acetic acid curing) filter; and petroleum ether washing filter cake to give a white solid, vacuum drying and then weight 35.6g, the yield of 83.6percent.
68%
for 16 h; Cooling with ice
1,4-dimethoxybenzene (1.66 g, 12.0 mmol) was dissolved in 25 mL glacial acetic acid and cooled in an ice bath. Bromine (1.3 mL, 25 mmol) was carefully added. The cooling bath was removed and the reaction was stirred for 16 h and then poured over ice. The reaction mixture was extracted 3 x with 100 mL of CHCl3. The combined organics were dried over MgSO4, filtered, and the solvents were removed under vacuum. The product was isolated via recrystallization in absolute ethanol to yield white needles (2.40 g, 68percent), mp 140-142 C (lit.5 mp 144-145 C). 1H NMR (CDCl3): δ 7.12 (s, 2H), 3.86 (s, 6H). The 1H NMR matches the known spectrum.5
63%
With bromine In acetic acid at 20℃; for 2 h;
To a solution of 1,4- dimethoxybenzene Q-8 (7.5 g, 53.57 mmol) in acetic acid (25 mL) was added a solution of bromine (17.4 g, 108.9 mmol) in acetic acid (5 mL) at room temperature. After stirring for 2h, the solution was cooled to 10 0C. The resulting fine precipitate was filtered, washed with water (20 mL), and dried under vacuum to obtain compound Q-9 (1Og, 63percent) as a white solid. TLC Rf = 0.5 (petroleum ether - EtOAc, 9.9:0.1); 1H NMR (CDCl3) δ 7.10 (s, 2H), 3.84 (s, 6H).
61%
With N-Bromosuccinimide In water; N,N-dimethyl-formamide at 20 - 80℃; for 6 h;
General procedure: To a stirred solution of starting compound (0.5–1.2 mmol) in DMF–H2O (95:5, v/v, 8–12 mL) mixture was added NBS (4.0–4.2 mmol) at room temperature. The contents were stirred at room temperature about 10 min and then heated for appropriate duration mentioned in Table 2. Progress of the reaction in every case was monitored by TLC analysis. After completion of the reaction, the reaction mixture was cooled to room temperature and quenched with aqueous NaHCO3 (20percent, 20–30 mL) solution. The insoluble precipitate was isolated by filtration and dried in vacuo. It was further purified by either recrystallization with ethyl acetate/n-hexane mixture or short pad silica gel column chromatography led to pure product.
Reference:
[1] Tetrahedron, 1999, vol. 55, # 36, p. 11127 - 11142
[2] Tetrahedron Letters, 1998, vol. 39, # 35, p. 6349 - 6350
[3] Organic Process Research and Development, 2016, vol. 20, # 2, p. 284 - 296
[4] Journal of the American Chemical Society, 2003, vol. 125, # 37, p. 11241 - 11248
[5] Journal of Materials Chemistry A, 2017, vol. 5, # 44, p. 22933 - 22938
[6] Journal of Materials Chemistry A, 2018, vol. 6, # 2, p. 374 - 382
[7] Synlett, 2005, # 17, p. 2664 - 2666
[8] Tetrahedron, 1997, vol. 53, # 30, p. 10357 - 10400
[9] New Journal of Chemistry, 2014, vol. 38, # 6, p. 2229 - 2232
[10] Journal of Organic Chemistry, 1998, vol. 63, # 11, p. 3764 - 3768
[11] Patent: WO2006/93467, 2006, A1, . Location in patent: Page/Page column 26
[12] Synthetic Communications, 2001, vol. 31, # 13, p. 2021 - 2027
[13] Patent: CN106397468, 2017, A, . Location in patent: Paragraph 0012; 0018; 0022
[14] Synthetic Communications, 1998, vol. 28, # 3, p. 499 - 505
[15] Chemical Communications, 2016, vol. 52, # 74, p. 11088 - 11091
[16] Tetrahedron, 2001, vol. 57, # 24, p. 5109 - 5121
[17] Journal of Organic Chemistry, 1980, vol. 45, # 3, p. 378 - 384
[18] Tetrahedron, 2015, vol. 71, # 2, p. 283 - 292
[19] Journal of Organic Chemistry, 2011, vol. 76, # 20, p. 8501 - 8507
[20] Patent: WO2010/129049, 2010, A1, . Location in patent: Page/Page column 111; 113
[21] Tetrahedron Letters, 2014, vol. 55, # 24, p. 3511 - 3515
[22] Synthetic Communications, 1998, vol. 28, # 11, p. 2087 - 2095
[23] Austral. J. scient. Res., 1949, vol. <A> 2, p. 595,599
[24] Chemische Berichte, 1878, vol. 11, p. 1036
[25] Journal of the Chemical Society, 1925, vol. 127, p. 2003
[26] Chemische Berichte, 1878, vol. 11, p. 1036
[27] Synthetic Communications, 2002, vol. 32, # 20, p. 3233 - 3239
[28] Macromolecules, 2002, vol. 35, # 13, p. 4975 - 4982
[29] Organic Letters, 2001, vol. 3, # 3, p. 445 - 447
[30] Canadian Journal of Chemistry, 2008, vol. 86, # 10, p. 976 - 981
[31] Polymer, 2010, vol. 51, # 3, p. 632 - 638
[32] Angewandte Chemie - International Edition, 2018, vol. 57, # 35, p. 11310 - 11315[33] Angew. Chem., 2018, vol. 130, p. 11480 - 11485,6
18
[ 150-78-7 ]
[ 2674-34-2 ]
[ 25245-34-5 ]
Reference:
[1] Monatshefte fuer Chemie, 1931, vol. 58, p. 92,104
[2] Chemical Papers, 2018, vol. 72, # 11, p. 2893 - 2898
19
[ 7789-69-7 ]
[ 150-78-7 ]
[ 2674-34-2 ]
[ 25245-34-5 ]
Reference:
[1] Chemische Berichte, 1931, vol. 58, p. 92,101
Reference:
[1] Journal of Medicinal Chemistry, 1975, vol. 18, # 12, p. 1201 - 1204
23
[ 108-24-7 ]
[ 150-78-7 ]
[ 1201-38-3 ]
Yield
Reaction Conditions
Operation in experiment
50%
at 20℃; for 1.5 h;
General procedure: An oven-dried vial was charged with anisole 1a (0.75 mmol, 1.0 equiv), acetic anhydride 2a (1.5 mmol, 2.0 equiv) and TFA (0.8 mL). The reaction mixture was stirred at room temperature and monitored by TLC or GC-MS. The reaction typically took 1.5 h to complete. Upon completion, aqueous sodium hydrogen carbonate was added and the aqueous phase was extracted with ethyl acetate (3 x 20 mL). The combined organic layers were dried over Na2SO4 and concentrated. The crude product was purified by silica gel column chromatography to afford ketone product 3a. Alternatively, the product can also be obtained without workup: upon completion, the solvent was removed under reduced pressure and the residue was subjected to silica gel flash column chromatography.
42%
With Hierarchical-Beta zeolite In neat (no solvent) at 119.84℃; for 4 h; Green chemistry
General procedure: In a typical acylation reaction, substrate, acetic anhydrideand catalyst (activated at 473 K) were mixed in a 25 mL roundbottom flask. Reactions were conducted at a desired temper-ature for a stipulated time period. The reaction mixture wasanalyzed using gas chromatography (GC) (Yonglin 6100; BP-5; 30 m × 0.25 mm × 0.25 m). Reactant conversion and productselectivity were obtained using GC. Products were confirmedusing GC–MS (Schimadzu GCMS-QP 2010 Ultra; Rtx-5 Sil Ms;30 m × 0.25 mm × 0.25 m). In most of the cases, products werealso confirmed by the authentic samples obtained from Aldrich(based on the retention time of the authentic sample in the GC anal-ysis). In the case of indole acylation, products were also confirmedusing NMR.
29%
at 80℃; for 0.5 h; Ionic liquid
Typical procedure: Bi(OTf)3 (0.0328 g, 0.05 mmol), [BMI][PF6] (0.5 g), anisole (0.108 g, 1 mmol), and acetic anhydride (0.102 g, 1 mmol) were stirred at 80 °C for 30 min. After cooling, the reaction mixture was extracted by diethyl ether (2 .x. 40 mL). The ether layer was decanted, washed with water, aqueous NaHCO3, and brine, and dried over MgSO4. The solvent was then removed on a rotary evaporator. The residue was purified by flash chromatography (n-hexane/ethyl acetate = 9:1) to give 4-methoxyacetophenone (0.120 g, 80percent yield).
Reference:
[1] Journal of Sulfur Chemistry, 2011, vol. 32, # 5, p. 463 - 473
[2] Tetrahedron Letters, 2018, vol. 59, # 10, p. 869 - 872
[3] Applied Catalysis A: General, 2015, vol. 493, p. 129 - 141
[4] Tetrahedron Letters, 2012, vol. 53, # 2, p. 222 - 224
[5] Journal of the American Chemical Society, 1945, vol. 67, p. 808
[6] Tetrahedron Letters, 1990, vol. 31, # 27, p. 3933 - 3936
[7] Synthetic Communications, 2011, vol. 41, # 5, p. 754 - 761
[8] European Journal of Organic Chemistry, 2012, # 16, p. 3132 - 3141
24
[ 75-36-5 ]
[ 150-78-7 ]
[ 1201-38-3 ]
Yield
Reaction Conditions
Operation in experiment
9%
With indium(III) tosylate In dodecane; nitromethane for 17 h; Schlenk technique; Reflux
General procedure: Into a Schlenk flask were introduced 20 mL of nitromethane,2 mmol of 1,3-dimethoxybenzene, 10 mol percent of catalyst and4 mmol of acetyl chloride, with 0.5 mmol of dodecane for GC monitoring. The solutions were heated at reflux. The reactionswere followed by gas chromatography, by analysis of aliquots.The products were obtained after extraction by diethyl ether andpurification by column chromatography. All products are knowncompounds.
Reference:
[1] European Journal of Organic Chemistry, 2012, # 16, p. 3132 - 3141
[2] Advanced Synthesis and Catalysis, 2010, vol. 352, # 17, p. 3031 - 3044
[3] Synthetic Communications, 2012, vol. 42, # 10, p. 1432 - 1444
[4] Advanced Synthesis and Catalysis, 2004, vol. 346, # 6, p. 599 - 602
[5] Journal of Organic Chemistry, 2004, vol. 69, # 20, p. 6953 - 6956
[6] Journal of Chemical Research, 2005, # 2, p. 80 - 81
[7] Helvetica Chimica Acta, 1981, vol. 64, # 8, p. 2741 - 2745
[8] Tetrahedron, 2015, vol. 71, # 38, p. 6813 - 6817
[9] Biochemical Preparations, 1955, vol. 4, p. 6,11
[10] Journal of Biological Chemistry, 1949, vol. 179, p. 365,367
[11] Recueil des Travaux Chimiques des Pays-Bas, 1945, vol. 64, p. 214,216
[12] Scientific Papers of the Institute of Physical and Chemical Research (Japan), 1932, vol. 18, p. 51,58[13] Chem. Zentralbl., 1932, vol. 103, # I, p. 2169
[14] Biochemical Preparations, 1955, vol. 4, p. 6,11
[15] Journal of Biological Chemistry, 1949, vol. 179, p. 365,367
[16] Recueil des Travaux Chimiques des Pays-Bas, 1945, vol. 64, p. 214,216
[17] Scientific Papers of the Institute of Physical and Chemical Research (Japan), 1932, vol. 18, p. 51,58[18] Chem. Zentralbl., 1932, vol. 103, # I, p. 2169
[19] Biochemical Preparations, 1955, vol. 4, p. 6,11
[20] Journal of Biological Chemistry, 1949, vol. 179, p. 365,367
[21] Recueil des Travaux Chimiques des Pays-Bas, 1945, vol. 64, p. 214,216
[22] Scientific Papers of the Institute of Physical and Chemical Research (Japan), 1932, vol. 18, p. 51,58[23] Chem. Zentralbl., 1932, vol. 103, # I, p. 2169
[24] Chemische Berichte, 1904, vol. 37, p. 3995
[25] Journal of Medicinal Chemistry, 1975, vol. 18, # 12, p. 1201 - 1204
[26] Helvetica Chimica Acta, 2003, vol. 86, # 8, p. 2754 - 2759
25
[ 64-19-7 ]
[ 150-78-7 ]
[ 1201-38-3 ]
Reference:
[1] Synthesis, 2004, # 13, p. 2165 - 2168
[2] Journal of Organic Chemistry, 1980, vol. 45, # 3, p. 501 - 506
[3] Journal of Organic Chemistry, 1996, vol. 61, # 26, p. 9546 - 9547
26
[ 64-19-7 ]
[ 150-78-7 ]
[ 705-15-7 ]
[ 1201-38-3 ]
Reference:
[1] Archiv der Pharmazie (Weinheim, Germany), 1955, vol. 288, p. 102,107,108
Reference:
[1] Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1980, p. 2894 - 2900
29
[ 7446-70-0 ]
[ 60-29-7 ]
[ 75-36-5 ]
[ 150-78-7 ]
[ 705-15-7 ]
[ 1201-38-3 ]
Reference:
[1] Gazzetta Chimica Italiana, 1948, vol. 78, p. 16,19
[2] Journal of the Chemical Society, 1939, p. 1922,1926
30
[ 150-78-7 ]
[ 75-65-0 ]
[ 7323-63-9 ]
Reference:
[1] Journal of Fluorine Chemistry, 1985, vol. 27, p. 401 - 410
31
[ 150-78-7 ]
[ 7323-63-9 ]
Reference:
[1] Journal of the American Chemical Society, 1942, vol. 64, p. 937
32
[ 507-20-0 ]
[ 150-78-7 ]
[ 21112-37-8 ]
[ 7323-63-9 ]
Reference:
[1] Bulletin of the Chemical Society of Japan, 2000, vol. 73, # 12, p. 2779 - 2782
33
[ 150-78-7 ]
[ 21112-37-8 ]
[ 7323-63-9 ]
Reference:
[1] Zhurnal Obshchei Khimii, 1946, vol. 16, p. 145,154[2] Chem.Abstr., 1947, p. 108
34
[ 115-11-7 ]
[ 150-78-7 ]
[ 21112-37-8 ]
[ 7323-63-9 ]
Reference:
[1] Zhurnal Obshchei Khimii, 1946, vol. 16, p. 145,154[2] Chem.Abstr., 1947, p. 108
35
[ 7664-93-9 ]
[ 64-19-7 ]
[ 150-78-7 ]
[ 75-65-0 ]
[ 7323-63-9 ]
Reference:
[1] Journal of the American Chemical Society, 1942, vol. 64, p. 937
36
[ 7446-70-0 ]
[ 98-95-3 ]
[ 115-11-7 ]
[ 150-78-7 ]
[ 21112-37-8 ]
[ 7323-63-9 ]
Reference:
[1] Zhurnal Obshchei Khimii, 1946, vol. 16, p. 145,154[2] Chem.Abstr., 1947, p. 108
37
[ 150-78-7 ]
[ 636-53-3 ]
Reference:
[1] Journal of the American Chemical Society, 1997, vol. 119, # 21, p. 4846 - 4855
38
[ 150-78-7 ]
[ 53581-81-0 ]
Reference:
[1] Journal of Medicinal Chemistry, 1975, vol. 18, # 12, p. 1201 - 1204
39
[ 150-78-7 ]
[ 25245-34-5 ]
Yield
Reaction Conditions
Operation in experiment
90%
With N-Bromosuccinimide In neat (no solvent) at 20℃; for 1.5 h; Milling; Green chemistry
General procedure: 1-Methoxy-3,5-dimethylbenzene(100mg, 0.73 mmol), N-Bromosuccinimide (NBS,260 mg,1.46 mmol) and one ball (5 mmdiameter, stainless steel) were transferred to a milling jar (10 mL, stainlesssteel). The ball-milling operation was performed and the progress of reaction was monitored by TLC/1H NMR.[1]After completion, the reaction mixture was transferred into 30 mL ethyl acetate and cooled at 0 °C. The product was isolated as filtrate upon paper filtration and waste succinimide as precipitate. The resulting filtrate were concentrated in vacuo to isolate 250 mg (yield: 85percent) of 2b as colourless powder. To test the efficiency in large scale, the reaction was also performed for the mono-bromination of 1-methoxy-3,5-dimethylbenzene in 1.3 g scale for 1 h and the product was isolated in 87percent yield.[1] The milling apparatus was stopped and small portion of the sample was collected from the reaction jar to study either TLC/ proton NMR. Following, the reaction was started again andthis operation time was excluded for reporting the reaction timing.
90%
With N-Bromosuccinimide In neat (no solvent) at 20℃; for 1.5 h; Milling; Green chemistry
General procedure: 1-Methoxy-3,5-dimethylbenzene (100mg, 0.73 mmol), N-Bromosuccinimide (NBS,260 mg,1.46 mmol) and one ball (5 mmdiameter, stainless steel) were transferred to a milling jar (10 mL, stainlesssteel). The ball-milling operation was performed and the progress of reactionwas monitored by TLC/1H NMR.[1]After completion, the reaction mixture was transferred into 30 mL ethyl acetateand cooled at 0 °C. The product was isolated as filtrate upon paper filtrationand waste succinimide as precipitate. The resulting filtrate were concentrated in vacuoto isolate 250 mg (yield: 85percent) of 2bas colourless powder. To test the efficiency in largescale, the reaction was also performed for the mono-bromination of1-methoxy-3,5-dimethylbenzene in 1.3 g scale for 1 h and the product wasisolated in 87percent yield.[1] Themilling apparatus was stopped and small portion of the sample was collectedfrom the reaction jar to study either TLC/ proton NMR. Following, the reaction was started again andthis operation time was excluded for reporting the reaction timing.
75%
at 50℃; for 6 h;
Synthesis of 2-bromo-1,4-dimethoxybenzene0.28 g (2.03 mmol; manufactured by Tokyo Chemical Industry Co., Ltd.) of 1,4-dimethoxybenzene and 0.98 g (2.09 mmol) of DITB obtained in Example 1 as a brominating agent and 4 mL of acetic acid were added to a test tube , And the mixture was stirred at 50 ° C. for 6 hours. After completion of the reaction, quantitative determination using gas chromatography (internal standard substance: chlorobenzene) confirmed the formation of the target product in a yield of 75percent.
73%
With bromine; acetic acid In methanol; chloroform at 0℃; for 3 h;
Example 1 : Preparation of 2,5-dimethoxybromobenzene (1); [00101] In a one liter round-bottom flask, a solution of bromine (16.0 g, 100 mmol) in acetic acid (50 ml) was added dropwise to a solution of 1 ,4- dimethoxybenzene (13.8 g, 100 mmol) in chloroform and methanol (400 ml) at 00C. After stirring for 3 hours, 500 ml of saturated Na2CO3 solution was added. The organic layer was washed with water, brine and dried over sodium sulfate. After the solvent was removed on a rotary evaporator, the residue was distilled under reduced pressure to yield 15.8 g of 2,5- dimethoxybromobenzene (yield 73percent) 1HNMR (CDCI3) 57.148 (s, 1 H), 6.859 EPO <DP n="28"/>(s, 2 H), 3.869 (s, 3 H), 3.785 (s, 3 H).
67 %Chromat.
With carbon dioxide; oxygen; lithium bromide; copper(ll) bromide In water at 100℃; for 12 h; Autoclave; Green chemistry
General procedure: A mixture of substrate (1 mmol), CuBr2 (22.4 mg, 10 molpercent), LiBr (130.3 mg, 1.5 equiv.), and 0.05 mL of water was placed in a 50 mL stainless steel autoclave equipped with an inner glass tube in room temperature. CO2 (4 MPa) and O2 (1 MPa) were subsequently introduced into the autoclave and the system was heated under the predetermined reaction temperature for 15 min to reach the equilibration. Then the final pressure was adjusted to the desired pressure by introducing the appropriate amount of CO2. The mixture was stirred continuously for the desired reaction time. After cooling, products were diluted with acetone and analyzed by gas chromatograph (Shimadzu GC-2014) equipped with a capillary column (RTX-17 30 m × 25 μm and RTX-wax 30 m × 25 μm) using a flame ionization detector by comparing the retention times of authentic samples. The residue was purified by column chromatography on silica gel (200–300 mesh, eluting with petroleum ether/ethyl acetate from petroleum ether to 50:1) to afford the desired product. The isolated products were further identified with NMR spectra (Bruker 400 MHz) and GC–MS or GCD, which are consistent with those reported in the literature.
90 %Chromat.
With ammonium metavanadate; perchloric acid; tetrabutylammomium bromide; dihydrogen peroxide In chloroform; water at 20℃; for 0.416667 h;
General procedure: NH4VO3 (5 molpercent) and H2O2 (200 molpercent) were placed in a flask. After complete dissolution of the catalyst, TBAB (3 mmol) was added and the mixture was stirred at room temperature. Then, Et2O (10 ml) and aromatic substrate (1 mmol) were added to the mixture. Finally, by slow drip, 1 ml of 1N HClO4 solution was added. After adding the acid, the colour of the reaction changed from yellow to red due to the formation of oxomonoperoxovanadium. Conversion was followed by TLC and determined by GC. The phases were separated and the aqueous phase was extracted with CH2Cl2 (15 ml x3). The organic phases were pooled, washed with brine, dried over Na2SO4 and filtered. The solvent was removed under reduced pressure and the resulting crude product was purified by column chromatography with Hex:AcOEt.
Reference:
[1] Helvetica Chimica Acta, 1983, vol. 66, # 4, p. 1068 - 1077
[2] Helvetica Chimica Acta, 1983, vol. 66, # 4, p. 1068 - 1077
[3] Journal of Organic Chemistry, 2002, vol. 67, # 13, p. 4487 - 4493
[4] Angewandte Chemie - International Edition, 2010, vol. 49, # 11, p. 2028 - 2032
[5] Tetrahedron Letters, 2003, vol. 44, # 9, p. 1815 - 1817
[6] Canadian Journal of Chemistry, 2009, vol. 87, # 2, p. 440 - 447
[7] Dalton Transactions, 2011, vol. 40, # 40, p. 10481 - 10490
[8] Chemistry Letters, 2003, vol. 32, # 10, p. 932 - 933
[9] Synthetic Communications, 1998, vol. 28, # 11, p. 2087 - 2095
[10] Tetrahedron Letters, 2004, vol. 45, # 25, p. 4887 - 4890
[11] Phosphorus, Sulfur and Silicon and the Related Elements, 2005, vol. 180, # 5-6, p. 1235 - 1240
[12] Acta Chemica Scandinavica, 1999, vol. 53, # 9, p. 714 - 720
[13] Tetrahedron, 2008, vol. 64, # 40, p. 9619 - 9624
[14] Tetrahedron Letters, 2014, vol. 55, # 13, p. 2154 - 2156
[15] Tetrahedron Letters, 2015, vol. 55, # 13, p. 2154 - 2156
[16] Tetrahedron Letters, 1998, vol. 39, # 35, p. 6349 - 6350
[17] Tetrahedron, 1999, vol. 55, # 36, p. 11127 - 11142
[18] Journal of Organic Chemistry, 2010, vol. 75, # 24, p. 8701 - 8704
[19] Journal of Chemical Research, 2006, # 6, p. 366 - 368
[20] Synthesis, 2011, # 2, p. 207 - 209
[21] Journal of Chemical Research, Miniprint, 2000, # 3, p. 417 - 429
[22] Synthetic Communications, 2001, vol. 31, # 13, p. 2021 - 2027
[23] Bioorganic and Medicinal Chemistry Letters, 2006, vol. 16, # 10, p. 2637 - 2640
[24] Advanced Synthesis and Catalysis, 2011, vol. 353, # 17, p. 3187 - 3195
[25] International Journal of Chemical Kinetics, 2016, vol. 48, # 2, p. 98 - 105
[26] Patent: JP2018/162218, 2018, A, . Location in patent: Paragraph 0039; 0040; 0041
[27] Tetrahedron, 2007, vol. 63, # 41, p. 10127 - 10132
[28] Patent: WO2006/93467, 2006, A1, . Location in patent: Page/Page column 25-26
[29] Australian Journal of Chemistry, 2000, vol. 53, # 4, p. 245 - 256
[30] Tetrahedron Letters, 2007, vol. 48, # 45, p. 7969 - 7973
[31] Bulletin of the Chemical Society of Japan, 1989, vol. 62, # 2, p. 591 - 593
[32] Synthetic Communications, 2007, vol. 37, # 8, p. 1381 - 1388
[33] Tetrahedron, 1982, vol. 38, # 8, p. 1105 - 1112
[34] Bulletin de la Societe Chimique de France, 1981, vol. 1, # 1-2, p. 42 - 48
[35] Justus Liebigs Annalen der Chemie, 1944, vol. 556, p. 1,7
[36] Austral. J. scient. Res., 1949, vol. <A> 2, p. 595,597, 598
[37] Rev. Fac. Cienc. quim. Univ. La Plata, 1950, vol. 25, p. 49,53
[38] Journal of Organic Chemistry, 1949, vol. 14, p. 911
[39] Chemische Berichte, 1890, vol. 23, p. 3255
[40] Ukrainskii Khimicheskii Zhurnal (Russian Edition), 1957, vol. 23, p. 341[41] Chem.Abstr., 1958, p. 4599
[42] Phosphorus, Sulfur and Silicon and the Related Elements, 1992, vol. 68, # 1-4, p. 261 - 292
[43] Synthetic Communications, 1999, vol. 29, # 4, p. 591 - 597
[44] Catalysis Today, 2012, vol. 194, # 1, p. 38 - 43
[45] Tetrahedron Letters, 2016, vol. 57, # 50, p. 5644 - 5648
40
[ 150-78-7 ]
[ 2674-34-2 ]
[ 25245-34-5 ]
Reference:
[1] Monatshefte fuer Chemie, 1931, vol. 58, p. 92,104
[2] Chemical Papers, 2018, vol. 72, # 11, p. 2893 - 2898
41
[ 7789-69-7 ]
[ 150-78-7 ]
[ 2674-34-2 ]
[ 25245-34-5 ]
Reference:
[1] Chemische Berichte, 1931, vol. 58, p. 92,101
42
[ 150-78-7 ]
[ 51560-21-5 ]
Yield
Reaction Conditions
Operation in experiment
97%
With iodine; periodic acid In methanol at 70℃; for 4 h; Inert atmosphere
Following the procedure by Ko et al,3 a solution of H5106 (2.92 g, 12.5 mmol) in methanol (25 mL) was stirred for 10 mm, then iodine (6.38 g, 25.0 mmol) was added to the mixture. 1,4-Dimethoxybenzene 8 (2.70 g, 20.0 mmol) was addedand the mixture was then heated at 70 °C for 4 h. The mixture was poured into a solution of Na55203 (5.00 g, 31.6 mmol) in water (50 mL). The solution was filtered and the precipitate was washed with methanol (20 mL), redissolved in CH2CI2 (20 mL) and filtered through a sintered funnel and the filtrate was evaporated in vacuo to afford title product 9 as a white solid (7.52 g, 97percent). 1H NMR (400 MHz; CDCI3)3.82 (6H, s, CH3), 7.19 (2H, s, Ar). The 1H NMR data was in agreement with literature values.4
94%
With iodine; periodic acid In methanol for 4 h; Reflux
Periodic acid (14.63 g, 64.2 mmol) was dissolved in 100 mL of methanol, added elemental iodine (31.82 g, 125 mmol), stirred for 10 minutes at room temperature, was added 1,4-bis (methyloxy) benzene (13.82 g, 100 mmol), the reaction was heated at reflux for 4 h.The reaction solution was poured into saturated sodium thiosulfate solution and a white solid was precipitated, filtered, washed with a little cold methylene chloride and methanol successively to give B as a white solid, 94percent yield.
77%
With potassium iodate; sulfuric acid; iodine; acetic acid In water for 24 h; Reflux
1,4-dimethoxybenzene (5, 5.314 g, 38.46 mmol), iodineresublimedcrystals (11.715 g, 46.16 mmol) and potassium iodate(4.116 g, 19.23 mmol) were dissolved in 131 mL of CH3COOH:H2-SO4:H2O (120:1:10). The reaction mixturewas allowed to stir underreflux for 24 h to obtain a dark reddish solution. After this, 200 mLof a saturated solution of sodium sulfite was added inducing precipitationof the product. The pale yellow solid formed was filteredand washed with sodium sulfite, ethanol and chloroform to give abright white powder (77percent yield). m,p.: 173e175 C; Lit 171e174 C[38]. 1H NMR (400 MHz, CDCl3): d 3.76 (s, 6H, OCH3), 7.12 (s, 2H, H-3) ppm. 13C NMR (100 MHz, CDCl3): d 67.85, 164.15, 96.21,132.41 ppm.
71%
With sulfuric acid; iodine; iodic acid; acetic acid In tetrachloromethane for 12 h; Heating / reflux
Example 3.2; Synthesis of 2,5-diiodo- 1,4-dimethoxybenzene; <n="31"/>The reaction mixture, 1,4-dimethoxybenzene (5.00 g, 36.19 mmol), iodine (8.27 g, 32.58 mmol), HIO3 (3.90 g, 22.17 mmol), H2SO4 (30 percent) (11.7 ml), acetic acid (63.3 ml), in 15 ml of Tetrachloromethane was refluxed for 12 hours. Then, the mixture was cooled to room temperature, the solvent was concentrated at reduced pressure and the crude product was collected by filtration and washed with acetone. A white solid was isolated (10.02g, yield 71 percent).
52.3%
With sulfuric acid; dihydrogen peroxide; iodine In methanolReflux
Methanol (200ml) was placed in a round bottomed flask to which 1,4-dimethoxybenzene (2.76g, 20mmol) was added followed by iodine pellets (5.2g, 20mmol) and a catalytic amount of sulfuric acid. The flask was then brought to reflux and hydrogen peroxide (40ml, 40mmol) was slowly added over several minutes. The reaction mixture was refluxed for several hours until white crystals spontaneously formed. The mixture was then cooled, filtered and the crystals washed with cold methanol. Further recrystallization was carried out in methanol to yield 1,4-diiodo2,5-dimethoxybenzene (4.1g, 52.3percent).
Reference:
[1] Patent: WO2018/47101, 2018, A1, . Location in patent: Page/Page column 68; 73
[2] Synthetic Communications, 2002, vol. 32, # 20, p. 3233 - 3239
[3] Patent: CN107573251, 2018, A, . Location in patent: Page/Page column 2; 5; 6
[4] Chemistry Letters, 1988, # 5, p. 795 - 798
[5] Macromolecules, 2015, vol. 48, # 15, p. 5155 - 5161
[6] Chemical Communications, 2012, vol. 48, # 7, p. 964 - 966
[7] Journal of Organic Chemistry, 2010, vol. 75, # 10, p. 3350 - 3357
[8] Dyes and Pigments, 2012, vol. 94, # 1, p. 88 - 98
[9] Journal of the American Chemical Society, 1995, vol. 117, # 26, p. 7017 - 7018
[10] Chemical Communications, 2002, # 21, p. 2526 - 2527
[11] Chemical Communications, 2006, # 18, p. 1983 - 1985
[12] Organic Process Research and Development, 2003, vol. 7, # 1, p. 98 - 100
[13] Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science (English Translation), 1981, vol. 30, # 4, p. 608 - 611[14] Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, 1981, # 4, p. 827 - 830
[15] Chemistry - A European Journal, 2009, vol. 15, # 48, p. 13356 - 13380
[16] Chemistry - A European Journal, 2011, vol. 17, # 34, p. 9320 - 9325
[17] Macromolecules, 2005, vol. 38, # 2, p. 234 - 243
[18] Journal of the American Chemical Society, 2013, vol. 135, # 14, p. 5408 - 5419
[19] Angewandte Chemie - International Edition, 2017, vol. 56, # 49, p. 15649 - 15653[20] Angew. Chem., 2017, vol. 129, p. 15855 - 15859,5
[21] Journal of Molecular Structure, 2017, vol. 1133, p. 448 - 457
[22] Organic and Biomolecular Chemistry, 2014, vol. 12, # 29, p. 5442 - 5447
[23] Journal of the American Chemical Society, 2001, vol. 123, # 9, p. 1828 - 1833
[24] Synthesis, 1995, # 10, p. 1273 - 1277
[25] Journal of the American Chemical Society, 2001, vol. 123, # 27, p. 6714 - 6715
[26] Patent: WO2008/96239, 2008, A1, . Location in patent: Page/Page column 28-29
[27] Chemical Communications, 2017, vol. 53, # 54, p. 7628 - 7631
[28] RSC Advances, 2016, vol. 6, # 51, p. 45001 - 45008
[29] Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1986, vol. 25, p. 1004 - 1005
[30] Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1986, vol. 25, p. 1004 - 1005
[31] Macromolecules, 2010, vol. 43, # 5, p. 2137 - 2144
[32] Synthetic Communications, 2013, vol. 43, # 17, p. 2280 - 2285
[33] Journal of the American Chemical Society, 2016, vol. 138, # 51, p. 16703 - 16710
[34] Chemistry - A European Journal, 2011, vol. 17, # 5, p. 1473 - 1484
[35] Indian Journal of Chemistry, Section B: Organic Chemistry Including Medicinal Chemistry, 1986, vol. 25, p. 1004 - 1005
[36] Tetrahedron Letters, 2016, vol. 57, # 16, p. 1739 - 1742
[37] Journal of Medicinal Chemistry, 1984, vol. 27, # 8, p. 1071 - 1077
[38] Journal of the Chemical Society, 1953, p. 713
[39] Journal of the Chemical Society, 1916, vol. 109, p. 1087
[40] Journal of Physical Chemistry, 1995, vol. 99, # 14, p. 4886 - 4893
[41] Austral. J. scient. Res., 1949, vol. <A> 2, p. 595,596
[42] Organic Letters, 2008, vol. 10, # 7, p. 1341 - 1344
[43] Angewandte Chemie - International Edition, 2009, vol. 48, # 51, p. 9646 - 9651
[44] Polymer, 2010, vol. 51, # 15, p. 3425 - 3430
[45] Polymer, 2011, vol. 52, # 12, p. 2537 - 2541
[46] Synlett, 2012, vol. 23, # 5, p. 778 - 782
[47] Advanced Functional Materials, 2012, vol. 22, # 5, p. 1076 - 1086
[48] Crystal Growth and Design, 2013, vol. 13, # 11, p. 4760 - 4768
[49] Patent: CN104151174, 2016, B, . Location in patent: Paragraph 0011; 0013; 0014; 0015
[50] Patent: WO2016/115362, 2016, A1, . Location in patent: Paragraph 0098
[51] Patent: CN104031108, 2016, B, . Location in patent: Paragraph 0085-0087; 0120-0122; 0143-0145
[52] Patent: CN104893714, 2016, B, . Location in patent: Paragraph 0100-0103
[53] Chemical Communications, 2017, vol. 53, # 68, p. 9414 - 9417
[54] Journal of the American Society for Mass Spectrometry, 2017, vol. 28, # 12, p. 2548 - 2560
43
[ 150-78-7 ]
[ 51560-21-5 ]
[ 90064-46-3 ]
Reference:
[1] Organic Process Research and Development, 2003, vol. 7, # 1, p. 98 - 100
44
[ 150-78-7 ]
[ 2100-42-7 ]
[ 51560-21-5 ]
[ 25245-35-6 ]
Reference:
[1] Organic Process Research and Development, 2003, vol. 7, # 1, p. 98 - 100
45
[ 150-78-7 ]
[ 51560-21-5 ]
[ 25245-35-6 ]
Reference:
[1] Organic Process Research and Development, 2008, vol. 12, # 6, p. 1130 - 1136
[2] Chemische Berichte, 1908, vol. 41, p. 4424
[3] Chemical Communications, 2006, # 36, p. 3794 - 3796
[4] Patent: WO2006/73124, 2006, A1, . Location in patent: Page/Page column 17-18; 24
46
[ 150-78-7 ]
[ 14753-51-6 ]
Reference:
[1] Macromolecules, 2002, vol. 35, # 13, p. 4975 - 4982
[2] Patent: CN106397468, 2017, A,
47
[ 150-78-7 ]
[ 4640-29-3 ]
Reference:
[1] Zeitschrift fuer Naturforschung, Teil B: Anorganische Chemie, Organische Chemie, 1983, vol. 38, # 7, p. 866 - 872
48
[ 68-12-2 ]
[ 150-78-7 ]
[ 5312-97-0 ]
Yield
Reaction Conditions
Operation in experiment
92%
Stage #1: With n-butyllithium In tetrahydrofuran; hexane at 0℃; for 2 h; Stage #2: at 0℃; for 2 h; Stage #3: With ammonia; iodine In tetrahydrofuran; hexane; water at 0 - 20℃; for 2 h;
General procedure: n-Butyllithium (1.67 M solution in hexane, 2.9 mL, 4.8 mmol) was added dropwise into a solution of 1,3-dimethoxybenzene (0.55 g, 4.0 mmol) in THF (5 mL) at 0 °C and the mixture was stirred for 2 h at the same temperature. Then, DMF (0.34 mL, 4.4 mmol) was added to the mixture and the obtained mixture was stirred at 0 °C. After 2 h at the same temperature, aq NH3 (8 mL, 120 mmol) and I2 (1.12 g, 4.4 mmol) were added and stirred for 2 h at rt. The reaction mixture was quenched with satd aq Na2SO3 (15 mL) and was extracted with Et2O (3.x.20 mL). The organic layer was washed with brine and dried over Na2SO4 to provide 2,6-dimethoxybenzonitrile in over 80percent purity. The product was purified by a short column chromatography on silica gel (Hexane/EtOAc=3:1) to give pure 2,6-dimethoxybenzonitrile in 91percent yield as a colorless solid.
Stage #1: at 0℃; for 0.5 h; Stage #2: at 100℃; for 10 h; Stage #3: With ammonia; iodine In tetrahydrofuran; water; N,N-dimethyl-formamide at 20℃; for 3 h;
General procedure: To an ice cooled solution of N-methylformanilide (2.2 mmol) was added dropwise diphosphoryl chloride (2.2 mmol). The solution was stirred for 30 min at 0 °C, and then 1,2-dimethoxybenzene (276.3 mg, 2 mmol) in DMF (1.0 mL) was added dropwise. After being stirred for 10 h at 100 °C, I2 (1015.2 mg, 4 mmol), aq NH3 (4 mL, 28-30percent) and THF (1 mL) were added to the reaction mixture. The obtained mixture was stirred for 3 h at rt. After the reaction, the mixture was poured into aq satd Na2SO3 solution and extracted with CHCl3 (3.x.20 mL). The organic layer was dried over Na2SO4, filtered, and evaporated. The product was purified by flash short column chromatography (Hexane:AcOEt=3:1) to afford 3,4-dimethoxybenzonitrile as a white solid in 92percent yield.
Reference:
[1] Zeitschrift fuer Naturforschung, Teil B: Anorganische Chemie, Organische Chemie, 1983, vol. 38, # 7, p. 866 - 872
[2] Justus Liebigs Annalen der Chemie, 1906, vol. 344, p. 46[3] Chemische Berichte, 1905, vol. 38, p. 796
51
[ 506-68-3 ]
[ 150-78-7 ]
[ 5312-97-0 ]
Reference:
[1] Helvetica Chimica Acta, 1920, vol. 3, p. 266
52
[ 143-33-9 ]
[ 150-78-7 ]
[ 5312-97-0 ]
[ 874-90-8 ]
Reference:
[1] Bulletin de la Societe Chimique de France, 1989, # 2, p. 156 - 167
53
[ 150-78-7 ]
[ 1758-25-4 ]
Reference:
[1] Nippon Kagaku Zasshi, 1958, vol. 79, p. 1110,1112, 1113[2] Chem.Abstr., 1960, p. 5557
[3] Journal of the Chemical Society, Perkin Transactions 1: Organic and Bio-Organic Chemistry (1972-1999), 1990, # 4, p. 1041 - 1045
54
[ 105-39-5 ]
[ 150-78-7 ]
[ 1758-25-4 ]
Reference:
[1] Journ. of Physiol., vol. 29, p. XIII[2] J. Th., 1904, p. 106
55
[ 108-24-7 ]
[ 150-78-7 ]
[ 1758-25-4 ]
Reference:
[1] Journal of the Indian Chemical Society, 1967, vol. 44, # 5, p. 398 - 399
56
[ 121-43-7 ]
[ 150-78-7 ]
[ 107099-99-0 ]
Reference:
[1] Journal of the American Chemical Society, 1994, vol. 116, # 17, p. 7895 - 7896
57
[ 150-78-7 ]
[ 107099-99-0 ]
Reference:
[1] Journal of the Chemical Society, Dalton Transactions, 2002, # 22, p. 4224 - 4235
[2] Chemistry - A European Journal, 2000, vol. 6, # 1, p. 123 - 128
58
[ 73183-34-3 ]
[ 150-78-7 ]
[ 1073339-07-7 ]
Reference:
[1] Chemical Communications, 2010, vol. 46, # 18, p. 3170 - 3172
[2] Chemical Communications, 2010, vol. 46, # 18, p. 3170 - 3172
(+/-)-cis-2-(3,6-dimethoxy2-fluorophenyl) cyclopropylamine[ No CAS ]
[ 82830-49-7 ]
Yield
Reaction Conditions
Operation in experiment
With n-butyllithium; In tetrahydrofuran; hexane; ethyl acetate;
EXAMPLE 61 (+,-)-N-(cis-2-(3,6-dimethoxy-2-fluorophenyl)-cyclopropyl)-N'-(5-chloropyrid-2-yl)-urea To a solution of 1,4-dimethoxybenzene (15.0 g, 0.109 mol) in 300 mL of dry THF was added 2.5M n-butyllithium (45.6 mL, 0.114 mol) at room temperature under nitrogen. After addition was complete, the solution was stirred for 1 hr. The mixture was cooled to -70 C. and N-fluorobenzenesulfonimide (36.0 g, 0.114 mol) in 150 mL of THF was added slowly, keeping the temperature below -60 C. The solution was allowed to warm to room temperature during the night. 100 mL of NH4 Cl (sat) was added and the mixture was extracted with diethyl ether/THF. The organic phase was washed with 1M NaOH (2*60 mL), dried over MgSO4 and evaporated. Column chromatography (silica gel, n-hexane followed by 1, 5 and 10% EtOAc in n-hexane) provided 11.43 g of a mixture of 1,4-dimethoxy-2-fluorobenzene and 1,4-dimethoxybenzene (4.3:1). This mixture was reacted in a manner analogous to Examples 362, 375 and 348 of WO 93/03022 to give (+,-)-cis-2-(3,6-dimethoxy2-fluorophenyl) cyclopropylamine.
Examples 1 to 13 To 5 ml of water were added 1.12 g (10 mmoles) of 1,3-cyclohexanedione and the each base shown in Table 1, and then 2 ml of 40percent aqueous solution of chloroacetoaldehyde was added thereto. The resulting mixture was stirred at room temperature for 2 hours. To the reaction mixture was added about 10 ml of ethyl acetate, and then the reaction mixture was acidified with 0.5 to 1 ml of sulfuric acid and stirred for 30 minutes. The resulting ethyl acetate layer was analyzed by gas-liquid chromatography (hereinafter referred to as 'GLC') (SE30 10percent 1.2 m *3 mmphi glass column, 130°C) using p-dimethoxybenzene as an internal standard. The obtained each result is shown in Table 1. It was proved from the results of the GLC that 4-oxo-4,5,6,7-tetrahydrobenzofuran was produced in a yield shown in Table 1, in each Example.
<strong>[658-93-5]3,4</strong>-Difluorophenylacetic acid (3.0 g, 17.4 mmol) and 1 ,4-dimethoxybenzene (3.6 g,26.1 mmol) in polyphosphoric acid (50 g) was heated at 72 C for 3 h. The reaction was cooled to 50 C, and H20 (70 mL) was added. The resulting mixture was extracted with ethyl acetate (2 x 100 mL). The organic layers were combined, washed with brine, dried over Na2S04, and concentrated under reduced pressure. The crude material was purified on a silica gel column to give 2-(<strong>[658-93-5]3,4</strong>-difluorophenyl)-l-(2,5-dimethoxyphenyl)ethanone (1.3 g) as a pale yellow solid. H NMR (300MHz, DMSO-de): delta 7.40-7.25 (m, 2H), 7.14-7.10 (m, 3H), 7.08-7.7.03 (m, 1H), 4.29 (s, 2H), 3.86 (s, 3H), 3.73 (s, 3H).
1-(2,5-dimethoxyphenyl)-2-(3-fluoro-4-methoxyphenyl)ethanone[ No CAS ]
Yield
Reaction Conditions
Operation in experiment
56%
With polyphosphoric acid; at 75℃; for 5h;
1,4-dimethoxybenzene (13.5 g, 97.7 mmol) and <strong>[452-14-2]2-<strong>[452-14-2](3-fluoro-4-methoxyphenyl)acetic acid</strong></strong> (10.0 g, 54.3 mmol) were added to polyphosphoric acid (55mL) at 75 C. The reaction was mixed thoroughly with a spatula until homogenous, heated at 75 C for 5 h, cooled to 50 C, and then quenched by portion-wise addition of water (55 mL) while stirring with a spatula. The mixture was cooled to 0 C, diluted with water (55 mL), and then extracted with ether (3x). The combined organic extracts were washed (brine), dried (Mg2S04), filtered, concentrated, and purified by silica gel chromatography (0-30% ethyl acetate in hexanes) to give the title compound (9.28 g, 56%) as an off-white solid. 1H NMR (400MHz, DMSO-d6): 5 7.13-7.11 (m, 2H), 7.10-7.02 (m, 3H), 6.97-6.92 (m, 1H), 4.20 (s, 2H), 3.85 (s, 3H), 3.80 (s, 3H), 3.72 (s, 3H)