反応 #45870

反応方程式

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

収率 41.5%

溶媒

methanol

chloroform

chloroform

反応条件

後処理

1. 1
   抽出The aqueous layer was extracted twice with chloroform
2. 2
   洗浄washed with saturated brine
3. 3
   乾燥dried over anhydrous sodium sulfate
4. 4
   その他The insoluble matter was separated by filtration
5. 5
   その他the solvent was evaporated away
6. 6
   その他the resulting residue was purified by preparative TLC (eluent, chloroform

実験手順

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.

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