반응 #45870

반응 방정식

dimethylamine

acetic acid

sodium cyanoborohydride

sodium hydrogencarbonate

2-Cyclopropyl-5-methyl-7-(3-oxocyclopentyl)-6-phenyl-1,3-benzoxazole-4-carbonitrile

→

ammonia methanol

2-cyclopropyl-7-[(1R*,3R*)-3-(dimethylamino)cyclopentyl]-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile

수율 41.5%

용매

methanol

chloroform

chloroform

반응 조건

후처리

1. 1
   추출The aqueous layer was extracted twice with chloroform
2. 2
   세척washed with saturated brine
3. 3
   건조dried over anhydrous sodium sulfate
4. 4
   기타The insoluble matter was separated by filtration
5. 5
   기타the solvent was evaporated away
6. 6
   기타the resulting residue was purified by preparative TLC (eluent, chloroform

실험 절차

2-Cyclopropyl-5-methyl-7-(3-oxocyclopentyl)-6-phenyl-1,3-benzoxazole-4-carbonitrile (I-303) (44 mg, 0.12 mmol) was dissolved in chloroform (1 ml) and methanol (1 ml), and at 0° C., dimethylamine (2 M tetrahydrofuran solution) (247 μl, 0.49 mmol), acetic acid (29 μl, 0.49 mmol) and sodium cyanoborohydride (33 mg, 0.49 mmol) were added. The solution was gradually warmed up to room temperature, then stirred for 21 hours, and fractionated with chloroform and an aqueous saturated sodium hydrogencarbonate solution. The aqueous layer was extracted twice with chloroform. The organic layers were combined, washed with saturated brine, and dried over anhydrous sodium sulfate. The insoluble matter was separated by filtration, the solvent was evaporated away and the resulting residue was purified by preparative TLC (eluent, chloroform:7 N ammonia/methanol solution=97:3, v/v) to obtain 2-cyclopropyl-7-[(1R*,3R*)-3-(dimethylamino)cyclopentyl]-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile (#141) (9.6 mg, 20%) as a white solid. Next, 2-cyclopropyl-7-[(1R*,3S*)-3-(dimethylamino)cyclopentyl]-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile (#142) (26 mg, 55%) was obtained as a white solid.

출처