反应详情

Sodium cyanoborohydride (1.6 g) is added to a 0° solution of 1-[1,1-dimethylethoxycarbonyl]-4-(2-aminophenyl)piperazine (PREPARATION 13, 6.52 g) and acetaldehyde (1.48 ml) dissolved in methanol (65 ml). After 3 hr the reaction mixture is partially concentrated under reduced pressure. Then it is diluted with chloroform, washed with saturated aqueous sodium bicarbonate, saline, dried over anhydrous sodium sulfate and concentrated under reduced pressure to give the title compound, Rf =0.62 (ethyl acetate/hexane, 1/1), NMR (300 MHz, CDCl3) 7.04, 6.95, 6.66, 4.59, 3.70-3.50, 3.15, 2.82, 1.49 and 1.28δ.

1. concentrationAfter 3 hr the reaction mixture is partially concentrated under reduced pressure
2. additionThen it is diluted with chloroform
3. washwashed with saturated aqueous sodium bicarbonate, saline
4. dry with materialdried over anhydrous sodium sulfate
5. concentrationconcentrated under reduced pressure