Sodium cyanoborohydride → Tert-butyl 2-(1-benzhydrylazetidin-3-yl)hydrazinecarboxylate
Reaction equation
[C:1]1([CH:7]([C:21]2[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=2)[N:8]2[CH2:11][C:10](=[N:12][NH:13][C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[CH2:9]2)[CH:6]=[CH:5][CH:4]=[CH:3][CH:2]=1.C([BH3-])#N.[Na+]>C(O)(=O)C>[C:21]1([CH:7]([C:1]2[CH:2]=[CH:3][CH:4]=[CH:5][CH:6]=2)[N:8]2[CH2:11][CH:10]([NH:12][NH:13][C:14]([O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[O:15])[CH2:9]2)[CH:22]=[CH:23][CH:24]=[CH:25][CH:26]=1Participants
4
Procedure
To a stirred solution of tert-butyl 2-[1-(diphenylmethyl)azetidin-3-ylidene]hydrazinecarboxylate (Preparation 692, 15.8 g, 45 mmol) in acetic acid (126 ml) was added sodium cyanoborohydride (2.82 g, 45 mmol) portionwise at room temperature and stirred at room temperature for 4 hours. Then the reaction mixture was concentrated in vacuo. The pH was adjusted to 8-10 with 1M aqueous sodium hydroxide solution and extracted with dichloromethane (3×200 ml). The combined organic layer was washed with water (3×150 ml), saturated aqueous sodium chloride solution (150 ml), dried over anhydrous sodium sulphate and concentrated in vacuo. The crude product was triturated with diethyl ether to get 15 g (94%) of the title compound as a white solid.