Name: 5834-16-2|3-Methyl-2-thiophenecarboxaldehyde|85% (HPLC)
Brand: Ambeed
SKU: A1485919
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1
[ 5834-16-2 ]
[ 141-82-2 ]
[ 102696-70-8 ]

Yield	Reaction Conditions	Operation in experiment
91%	With piperidine; pyridine; at 100℃; for 16h;	To a stirred solution of aldehyde (40 mmol) in pyridine (50 mL) was added malonic acid (50 mmol) followed by piperidine (2 mL). The reaction mixture was heated to 100 C. for 16 h and concentrated under in vacuo. The resultant residue was poured onto aqueous 1N hydrochloric acid (100 mL). The solid was filtered off and dried under high vacuum; 3-(3-Methylthiophen-2-yl)acrylic acid (E-isomer) was prepared from 3-methylthiophene-2-carboxaldehyde following Method H in 91% yield. 1H NMR (300 MHz, CDCl3): 7.28 (d, J-=5.21 Hz, 1H), 6.86 (d, J=5.21 Hz, 1H), 6.14 (d, J=15.78 Hz, 1H), 2.34 (s, 3H).
59%	With piperidine; pyridine;Reflux;	General procedure: Title compounds were prepared, as illustrated in Scheme 1, by a Knoevenangel condensation of the suitable heteroarylaldehyde with malonic acid. Malonic acid (0.01 mol) was dissolved in 1.12 mL of pyridine and the heteroaldehyde (0.01 mol) and piperidine (0.01 mol) were added. The mixture was refluxed until the emission of CO2 stopped. Then the solution was poured into 2 N HCl and then on ice. The formed precipitate was collected by filtration and recrystallized from water or from 3:1 water/ethanol mixture. If no precipitate was formed an extraction with 3 × 100 mL CHCl3 or CH2Cl2 was made and the organic phase was collected, dried over MgSO4, and evaporated to dryness affording a residue that was recrystallized from aqueous ethanol.

Reference： [1]Patent: US2006/211603,2006,A1 .Location in patent: Page/Page column 39; 47-48
[2]European Journal of Medicinal Chemistry,2011,vol. 46,p. 191 - 200
[3]Journal of Organic Chemistry,1949,vol. 14,p. 405,409

2
[ 5834-16-2 ]
[ 79-19-6 ]
[ 5425-42-3 ]

Yield	Reaction Conditions	Operation in experiment
88%	In ethanol; water; at 60℃;	General procedure: To a solution of the appropriate aldehyde or ketone (1 eq.) in 50% aqueous ethanol (v/v), thiosemicarbazide (1 eq.) was added. The mixture was stirred at 60C for 2-12h, cooled at room temperature and diluted with water. The precipitate formed was collected and recrystallized from water and ethanol to give the desired product in 65-95% yield.
84%	In ethanol; water;	General procedure: A total of 1mM of the corresponding aldehyde11a-r and12a-k was dissolved in 2mL of ethyl alcohol.The resulting solution was slowly added dropwise with stirring to a solution of 1mM thiosemicarbazide in 2mL of distilled water.The precipitate that formed was filtered off,washed with water,then air dried.The thiosemicarbazones 13a-rand14a-k obtained were isolated in58- 93%yields.

Reference： [1]European Journal of Medicinal Chemistry,2018,vol. 146,p. 423 - 434
[2]Molecules,2019,vol. 24
[3]Journal of the American Chemical Society,1953,vol. 75,p. 988

3
[ 5834-16-2 ]
[ 632-16-6 ]

Yield	Reaction Conditions	Operation in experiment
89%	With potassium hydroxide; hydrazine hydrate; In diethylene glycol;	Step 1 2,3-Dimethylthiophene A stirred mixture of commercial 3-methylthiophenecarboxaldehyde (20 g, 0.159 mol), hydrazine hydrate (31 mL) and diethylene glycol (72 mL) was refluxed for 20 min. After cooling below 100 C., potassium hydroxide (22.9 g, 0.408 mol) was slowly added and the reaction mixture was heated at 125-130 C. for 1.5 h. The reaction mixture was cooled to ambient temperature, quenched with H2 O and extracted with ether. The combined ethereal extracts were washed with 5% aqueous HCl, brine, dried (MgSO4) and concentrated. Purification on silica gel eluding with pentane provided the title compound as an oil (15.81 g, 89%): 1 H NMR (CDC13) 6 6.97 (d, 1H, J=8 Hz), 6.77 (d, 1 H, J=8 Hz), 2.35 (s, 3 H), 2.14 (s, 3 H).
89%	With potassium hydroxide; hydrazine hydrate; In diethylene glycol;	Step 2 2,3-Dimethylthiophene A stirred mixture of commercial 3-methylthiophenecarboxaldehyde (20 g, 0.159 mol), hydrazine hydrate (31 mL) and diethylene glycol (72 mL) was refluxed for 20 min. After cooling below 100 C., potassium hydroxide (22.9 g, 0.408 mol) was slowly added and the reaction mixture was heated at 125 -130 C. for 1.5 h. The reaction mixture was cooled to ambient temperature, quenched with H2 O and extracted with ether. The combined ethereal extracts were washed with 5% aqueous HCl, brine, dried (MgSO4) and concentrated. Purification on silica gel eluding with pentane provided the title compound as an oil (15.81 g, 89%): 1 H NMR (CDCl3) delta 6.97 (d, 1H, J=8 Hz), 6.77 (d, 1 H, J=8 Hz), 2.35 (s, 3 H), 2.14 (s, 3 H).
89%	With potassium hydroxide; hydrazine hydrate; In water; diethylene glycol;	EXAMPLE 1 2.3-Dimethyl-thiophene A mixture of 3-methyl-thiophene-carboxaldehyde (20 g, 0.159 mol), hydrazine hydrate (31 mL) and diethylene glycol (72 mL) was heated to reflux for 20 min. After cooling below 100 C., potassium hydroxide (22.9 g, 0.408 mol) was added and the reaction mixture was heated at 125-130 C. for 1.5 h. The reaction mixture was cooled to room temperature and added to water. This aqueous mixture was extracted with ether and the ether phase was washed with 5% aqueous HCl and brine. After drying (magnisium sulfate) the solvent was removed and the oil was flash chromatograghed (pentane as eluent) to provide the title compound as an oil (15.81 g, 89%): NMR (CDCl3); delta6.97 (d, 1H, J=8 Hz), 6.77 (d, 1H, J=8 Hz), 2.35 (s, 3H), 2.14 (s, 3H).

		<strong>[5834-16-2]3-Methyl-2-thiophenecarboxaldehyde</strong> (Aldrich, 90% GC purity) (40 g) was dissolved in diethylene glycol (144 [ML)] and hydrazine hydrate (62 ml) was added slowly. The reac- tion mixture was refluxed (about [126C)] for 30 minutes. The solution was cooled to 30- [40C] and potassium hydroxide (46 g) was then added portionwise. The solution was then slowly heated to reflux and stirred at this temperature for one and a half hours. The reaction mixture was cooled to room temperature and poured into cold water (1 L), acidified to pH 2 with concentrated hydrochloric acid (about 150 mi) and extracted with methylene chloride [(2X100] [ML).] The combined organic phases were dried over anhy- drous sodium sulphate. The solid was filtered off and washed with methylene chloride (20 [ML)] and the 2, [3-DIMETHYLTHIOPHENE] solution was used directly without further purifi- cation (88.2% GC purity).
	With potassium hydroxide; hydrazine hydrate; In ethylene glycol;	2,3-dimethylthiophene (5). Heating a mixture of 3-methyl-2-thiophene carboxaldehyde, 4 (58.6 g, 464 mmole), 80% hydrazine hydrate (97 mL, 1.62 mole) and 200 mL ethylene glycol to an internal temperature of 130-160 C. caused hydrazine and water to distil. The reaction mixture was cooled to below 60 C. and the water-immiscible fraction of the distillate was returned to the flask. The addition of KOH (91.0 g, 1.62 mole) and reheating caused vigorous gas evolution when the temperature reached 90-100 C. Reflux continued for 15 minutes after gas evolution ceased; steam distillation then separated 5. Product in the distillate was extracted into ether, the extract washed with 6 N HCl, dried over CaC12 and evaporated. Distillation over sodium gave 5 as a colorless oil, bp 139.5-140.5, yield 39.8 g, 77%. 1H NMR (CDCl3) delta: 2.21, s, 3H, CH3; 2.41, s, 3H, CH3,; 6.84, d, J=5.1 Hz, 1H, H-4, 7.03, d, J=5.2 Hz, 1H, H-5. 13C NMR (CDCl3) delta: 13.0, 13.6, 120.6, 129.9, 132.6, 133.0.

Reference： [1]Patent: US6103708,2000,A
[2]Patent: US6121271,2000,A
[3]Patent: US6251936,2001,B1
[4]European Journal of Medicinal Chemistry,2000,vol. 35,p. 323 - 331
[5]Journal of Medicinal Chemistry,2002,vol. 45,p. 382 - 389
[6]Journal of Organic Chemistry,1949,vol. 14,p. 638,639
[7]Tetrahedron Letters,1987,vol. 28,p. 957 - 960
[8]Journal of Medicinal Chemistry,1992,vol. 35,p. 3012 - 3016
[9]Patent: WO2004/35562,2004,A1 .Location in patent: Page 13
[10]Synlett,2016,vol. 27,p. 131 - 135
[11]Patent: US2003/78248,2003,A1

4
[ 5834-16-2 ]
[ 23806-24-8 ]

Reference： [1]Journal of Organic Chemistry,1948,vol. 13,p. 635,637
[2]Journal of Organic Chemistry,1980,vol. 45,p. 4528 - 4530

5
[ 2346-00-1 ]
[ 5834-16-2 ]
2-[2-(3-methyl-thiophen-2-yl)-vinyl]-4,5-dihydro-thiazole [ No CAS ]

Reference： [1]Journal of medicinal chemistry,1970,vol. 13,p. 113 - 119

6
[ 5834-16-2 ]
[ 98-86-2 ]
(E)-3-(3-methylthiophen-2-yl)-1-phenylprop-2-en-1-one [ No CAS ]

Yield	Reaction Conditions	Operation in experiment
27.22%	With potassium hydroxide; In methanol; water; at 20℃;	General procedure: A mixture of desired substituted acetophenone (2a-g) (0.02 mol), 3-methyl-2-thiophene carboxaldehyde (1) (0.02 mol) and aqueous potassium hydroxide (30 %, 0.006 mol) was dissolved in methanol (25 mL). The reaction mixture was stirred at room temperature overnight, the solid product was separated, washed, dried to obtain the corresponding chalcones (3a-g) by re-crystallization. Completion of the reaction was monitored by TLC [16]. 2.1.2.1. (E)-3-(3-methylthiophen-2-yl)-1-phenylprop-2-en-1-one (3a) Yellow solid, yield: (1.99 g, 27.22 %). M.p: 56-61C IR(cm-1): 3089 (C-H-sp2 stretching of aromatic ring), 2925(CH-sp3), 1655 (C=O), 1583, 1572, 1445 (C=C aromaticring). 1H NMR (400 MHz, CDCl3): delta 2.40 ( s, 3H, H-6), 6.93(d, 1H, H-4, J = 4.8 Hz), 7.28-7.35 (m, 2H, H-5, H-alpha), 7.50-7.55 (m, 2H, H-3?, H-5?), 7.57-7.60 (m, 1H, H-4?), 8.02-8.10 (m, 3H, H-2?, H-6?and H-beta). 13C NMR (100 MHz, CDCl3): delta 14.34 (C-6), 119.69 (C-alpha), 127.39 (C-5), 128.38 (C-2?, C-6?), 128.62 (C-3?, C-5?), 131.49 (C-4), 132.73 (C-4?), 134.56(C-2), 135.62 (C-beta), 138.28 (C-1?), 142.89 (C-3), 189.83 (C=O).

Reference： [1]Letters in drug design and discovery,2018,vol. 15,p. 1202 - 1210
[2]Organic Magnetic Resonance,1980,vol. 14,p. 384 - 391
[3]European Journal of Organic Chemistry,2015,vol. 2015,p. 331 - 335

7
[ 5834-16-2 ]
[ 4271-96-9 ]
[ 83467-08-7 ]

Reference： [1]Tetrahedron,1982,vol. 38,p. 1673 - 1676

8
[ 5834-16-2 ]
[ 63826-56-2 ]

Yield	Reaction Conditions	Operation in experiment
99%	With sodium tetrahydroborate; In ethanol; toluene; at 0 - 20℃;	Step 1: (3-Methylthiophen-2-yl)methanolSodium borohydride (718 mg, 19.02 mmol) was added portionwise, at 0C, to a solution of 3-methylthiophene-2-carbaldehyde (2.0 g, 15.85 mmol) in a mixture of ethanol and toluene (1 : 1, 12 mL). The reaction mixture was stirred 2 hours at room temperature and then partitioned between ethyl acetate (15 mL) and water (15 mL). The aqueous layer was separated and extracted with ethyl acetate (3 x 45 mL). The combined organic phases were washed with a saturated solution of sodium chloride (1 x 10 mL), dried over sodium sulfate, filtered and concentrated under vacuum to give the title product as a pink oil (2.24 g, 99%).1 NMR (CDCI3, 400 MHz) : delta (ppm) : 7.16 (d, J = 5.2 Hz, 1H), 6.84 (d, J = 5.2 Hz, 1H), 4.76 (S, 2H), 2.23 (S, 3H).
95%	With sodium tetrahydroborate; In ethanol; at 0 - 20℃; for 1h;	As shown in Reaction Scheme 3, 3-methyl-2-thiophene-carboxaldehyde (40 g, 317 mmol) was dissolved in ethanol (500 mL) at 0 C., and sodium borohydride (22 g, 581 mmol) was then gradually added thereto. The solution was warmed to room temperature, followed by reaction for 1 hour. After completion of the reaction was confirmed by TLC, unreacted sodium borohydride was inactivated using water and aqueous ammonium chloride, followed by ethyl acetate extraction. An organic layer was washed with water (200 mL×2). The organic layer was separated, dried over anhydrous magnesium sulfate, and filtered under reduced pressure to remove the solvent, thus affording the title compound 3-methylthiophen-2-yl)methanol (3a). Yield: 95%.1H NMR (CDCl3, 400 MHz): 7.14 (d, 2H, J=8.6 Hz), 6.82 (d, 1H, J=5.2 Hz), 4.74 (s, 2H), and 2.22 (s, 3H).
95%		Step 1: Preparation of (3-methylthiophen-2-yl)methanol (3a)As shown in Reaction Scheme 3, 3-methyl-2-thiophene-carboxaldehyde (40 g, 317 mmol) was dissolved in ethanol (500 mL) at 0C, and sodium borohydride (22 g, 581 mmol) was then gradually added thereto. The solution was warmed to room temperature, followed by reaction for 1 hour. After completion of the reaction was confirmed by TLC, unreacted sodium borohydride was inactivated using water and aqueous ammonium chloride, followed by ethyl acetate extraction. An organic layer was washed with water (200 mL X 2). The organic layer was separated, dried over anhydrous magnesium sulfate, and filtered under reduced pressure to remove the solvent, thus affording the title compound 3-methylthiophen-2-yl)methanol (3a).Yield: 95%. <n="48"/>1H NMR (CDCl3, 400MHz): 7.14(d, 2H, J=8.6Hz), 6.82(d, IH, J=5.2Hz), 4.74(s, 2H), and 2.22(s, 3H).

89%		To a stirred solution of aldehyde (40 mmol) in a mixture of methanol (15 mL) and THF (50 mL) at 0 C. was added solid NaBH4 (40 mmol) portion wise over a 5 min period. The resultant reaction mixture was stirred at 0 C. for additional 30 min and quenched with addition of saturated NH4Cl solution. The aqueous layer was extracted with ether, the ether layer was dried over MgSO4, and concentrated in vacuo to yield the corresponding alcohol. The alcohol was used in the next step without further purification; (3-Methylthiophen-2-yl)methanol was obtained from 3-methylthiophene-2-carboxaldehyde in 89% yield according to Method D.
88%	With methanol; sodium tetrahydroborate; at 0℃; for 0.5h;	(45-1) Preparation of (3-methylthiophen-2-yl)methanol (Compound 3) 3-Methyl-2-thiophen-carboxaldehyde (1.00 g, 7.93 mmol) was dissolved in methanol (16 mL), and the reaction mixture was cooled to 0 C., and then sodium borohydride (0.60 g, 15.86 mmol) was added. The reaction mixture was stirred at room temperature for about 30 min, and water (30 mL) was sequentially added to the mixture. The resulting mixture was extracted with ethyl acetate. The extract was washed with saline, dried over sodium sulfate, and concentrated. The residue was purified by flash column chromatography (ethyl acetate:hexanes=20:80), to obtain the title compound (0.89 g, 88%). 1H NMR (300 MHz, CDCl3) delta 7.17 (d, 1H, thiophene), 6.84 (d, 1H, thiophene), 4.76 (d, 2H, J=4.92 Hz, CH2), 2.25 (s, 3H, CH3), 1.66 (t, 1H, J=5.43 Hz, OH); IR (neat): 3320, 3100, 3060, 2918, 2861, 1555, 1430, 1383, 1368, 1353, 1300, 1231, 1171, 1032, 996, 932, 876, 832, 703, 663 cm-1; MS (ESI+) m/z 128.19 [M+].
	With sodium borohydrid; In ethanol; acetone;	(a) 2-Hydroxymethyl-3-methylthiophene Sodium borohydride (166 mg) was added portionwise over 3 mins to a stirred solution of 3-methyl-2-thiophenecarbaldehyde (0.43 ml) in ethanol (5 ml). After 25 mins acetone (1 ml) was added and then after a further 5 mins the reaction mixture was concentrated to ca 5 ml. The residue was diluted with water (20 ml) and extracted with diethyl ether (20 ml, 2*10 ml). The combined extracts were dried and evaporated to a brown liquid (490 mg). The liquid was subjected to collumn chromatography on silica (70-230 mesh) (50 g) developing with chloroform. This gave a pale brown liquid, the title thiophene (351 mg), lambdamax 237 nm (E11 538).
	With sodium borohydrid; In ethanol;	EXAMPLE 50 2-hydroxymethyl-3-methylthiophene 0.95 G. (0.025 mol) of sodium borohydride were added in portions to a solution of 12.6 g. (0.1 mol) of 3-methylthiophene-2-carboxaldehyde in 150 ml. of ethanol. The resulting reaction mixture was stirred at room temperature for 0.5 hr., poured into ice water and extracted with ether. The organic phase was washed with saturated sodium chloride solution, dried and evaporated. The residue was distilled to yield 2-hydroxymethyl-3-methylthiophene, b.p. 46 C./0.3 mm.
	With sodium tetrahydroborate; In tetrahydrofuran; at 10 - 20℃; for 3h;	Sodium borohydride (6.0 g, 158.5 mmol, 2 equiv.) was suspended in dry tetrahydrofuran under an inert atmosphere. At 10 C. a solution of 3-methyl-thiophene-2-carbaldehyde (10 g, 79.2 mmol, 1 equiv.) in dry tetrahydrofuran was added dropwise. The mixture was stirred at room temp. for 3 hours. The reaction mixture was quenched with diluted acid and filtered. The filtrate was extracted with diethyl ether. The combined organic extracts were washed with brine, dried over magnesium sulfate dihydrate, filtered and evaporated. Kugelrohr distillation of the crude product gave 8.33 g of the title compound as a light yellow oil. GC-MS (EI) M=128
		Example 6262.1 62.2[04271 (3-Methylthiophen-2-yl)methanoI (62.2).; To a solution of 3- methylthiophene-2-carboxaldehyde 62.1 (3.17 g, 25.1 mmol) in MeOH (100 mL) was added NaBH4 (1.05 g, 27.6 mmol) as a solid in one portion. The mixture was stirred for 15 minutes at room temperature and concentrated. The residue was <n="186"/>suspended in IN HCl and extracted with EtOAc. The combined organic layers were washed with brine, dried (Na2SO4), and concentrated. The crude product was chromatographed on silica gel (0-35% EtOAc/hexane) to afford 62.2 as a pale yellow liquid. 1H NMR (400 MHz7 CDCl3) delta 7.17 (d, IH), 6.84 (d, IH)5 4.76 (s, 2H), 2.25 (s, 3H).
	With sodium tetrahydroborate; In methanol; at 0 - 35℃; for 12h;	(i) NaBH4, MeOH, 0C to 20-35C, 12h;

Reference： [1]Patent: WO2011/61214,2011,A1 .Location in patent: Page/Page column 90
[2]Patent: US2010/63041,2010,A1 .Location in patent: Page/Page column 30
[3]Patent: WO2008/108602,2008,A1 .Location in patent: Page/Page column 45-46; 28
[4]Patent: US2006/211603,2006,A1 .Location in patent: Page/Page column 39; 47
[5]Patent: US2011/196015,2011,A1 .Location in patent: Page/Page column 9
[6]Journal of Organic Chemistry,1991,vol. 56,p. 6337 - 6341
[7]Patent: US4399140,1983,A
[8]Patent: US4061656,1977,A
[9]Patent: US2007/281979,2007,A1 .Location in patent: Page/Page column 21
[10]Patent: WO2008/30520,2008,A1 .Location in patent: Page/Page column 184-185
[11]Patent: WO2013/80222,2013,A1 .Location in patent: Page/Page column 37-38

9
[ 616-44-4 ]
[ 68-12-2 ]
[ 6030-36-0 ]
[ 5834-16-2 ]

Yield	Reaction Conditions	Operation in experiment
		A solution of 3-methylthiophene (6.76 mL, 70 mmol) in ether (70 mL) was treated with n-butyllithium (2.5 M in hexanes, 28.6 mL, 71.4 mmol) at such a rate that a slight reflux was maintained. The reaction mixture was heated to reflux for 15 min and then DMF (7.0 mL, 91 mmol) in ether (30 mL) was added. After stirring for 4 h, the reaction was quenched with addition of satd aq NH4Cl (200 mL). The organic layer was separated, washed with brine and then H2O, dried over Na2SO4, and concentrated. Column chromatography (SiO2, 5-10% EtOAc/hexanes) provided a mixture of 4-methyl-thiophene-2-carbaldehyde and 3-methyl-thiophene-2-carbaldehyde (4.4:1, 8.1 g, 92%) as a light yellow oil. TLC (silica, 10% EtOAc/hexanes): Rf=0.55. For 4-methyl-thiophene-2-carbaldehyde: 1H NMR (CDCl3, 400 MHz): 9.95 (s, 1H), 7.58 (d, J=1.2 Hz, 1H), 7.37-7.35 (m, 1H), 2.32 (s, 3H). For 3-methyl-thiophene-2-carbaldehyde: 1H NMR (CDCl3, 400 MHz): 10.02 (s, 1H), 7.64 (d, J=4.6 Hz, 1H), 6.97 (d, J=4.6 Hz, 1H), 2.58 (s, 3H).
		4-Methyl-2-thiophenecarboxaldehyde A solution of 3-methylthiophene (58.90 g, 0.60 mol) (Fluka) in anhydrous ether (600 mL) was stirred and cooled in an ice-water bath. This solution was treated dropwise over 15 minutes with n-butyllithium in pentane (2 M, 450 mL, 0.90 mol) (Aldrich). After stirring for 2 hours at room temperature the mixture was cooled in an ice-water bath and treated dropwise over 5 minutes with N,N-dimethylformamide (48.24 g, 0.66 mol) (Fisher) followed by stirring at room temperature over night. The mixture was diluted with ether (600 mL) and washed with water and brine. After drying (sodium sulfate) ether was filtered and evaporated on a rotary evaporator without vacuum to give 114 g of red liquid. This liquid was purified by chromatography over a pad of silica gel 60 (1 Kg, 70-230 mesh) eluding with 40% dichloromethane-hexanes. Evaporation without vacuum gave a mixture of 4-methyl-2-thiophenecarboxaldehyde and 3-methyl-2-thiophenecarboxaldehyde (approximately 5:1) as a light red oil. (Yield 56.62 g, 74.7%).
		To a stirred solution of 3-methylthiophene (9.8 g, 100 mmol) in anhydrous THF (100 mL) at -78 C. was added n-BuLi (44 mL, 2.5 M solution in hexanes, 110 mmol) drop wise. After completion of addition, the reaction mixture was stirred at -78 C. for an additional 1 h, then quenched with DMF (20 mL). The reaction mixture was allowed to attain room temperature, concentrated in vacuo, and the residue was suspended in water. The aqueous layer was extracted with ether, the organic layer dried over MgSO4, filtered and concentrated. The resultant residue was purified on silica gel column chromatography using 10% ethyl acetate in hexanes as an eluent to afford 4-methylthiophene-2-carboxaldehyde (major product) and 3-methylthiophene-2-carboxaldehyde (minor product) (6.5 g, 3:1 ratio). This product was used without further purification in the subsequent step.

Reference： [1]Heterocycles,1995,vol. 40,p. 925 - 938
[2]Heterocycles,1995,vol. 40,p. 925 - 938
[3]Heterocycles,1995,vol. 40,p. 925 - 938
[4]Tetrahedron Letters,2000,vol. 41,p. 2749 - 2752
[5]Journal of Medicinal Chemistry,2005,vol. 48,p. 8289 - 8298
[6]Journal of Organic Chemistry,2007,vol. 72,p. 1634 - 1638
[7]Journal of Organic Chemistry,2007,vol. 72,p. 1031 - 1034
[8]Patent: US2004/48878,2004,A1 .Location in patent: Page/Page column 12
[9]Patent: US2005/256154,2005,A1 .Location in patent: Page/Page column 10
[10]Molecules,2010,vol. 15,p. 3121 - 3134
[11]Patent: US2006/211603,2006,A1 .Location in patent: Page/Page column 55

10
[ 3760-54-1 ]
[ 616-44-4 ]
[ 6030-36-0 ]
[ 5834-16-2 ]