反应详情

A solution of (RS)-1-(tert-butyloxycarbonyl)-3-carbamoylpiperazine (ref Bruce et al. Syn. Comm. 1995, 2673-84) (25 g, 0.109 mol) and benzaldehyde (11.1 ml, 0.109 mol) in 1,2-dichloroethane (550 ml) was stirred at room temperature for 1.5 h. Sodium triacetoxyborohydride (34.7 g, 0.163 mol) was added in one portion and the resultant stirred for a further 18 h. Dichloromethane (400 ml) was added and the mixture washed with saturated sodium hydrogen carbonate (600 ml). The organic layer was dried (Na2SO4) and evaporated in vacuo. The residue was chromatographed on silica gel eluting with 10-70% ethyl acetate in hexane to afford the title compound as a colourless solid (32.4 g, 93%).

1. washthe mixture washed with saturated sodium hydrogen carbonate (600 ml)
2. dry with materialThe organic layer was dried (Na2SO4)
3. customevaporated in vacuo
4. customThe residue was chromatographed on silica gel eluting with 10-70% ethyl acetate in hexane