反应详情

A solution of 0.75 g (3.10 mmol) of 3-((S)-3-methyl-2-oxo-piperazin-1-yl)-propionic acid tert-butyl ester with 0.1HCl in 16 ml of dichloromethane was treated at 0° C. with 0.70 g (3.70 mmol) of 3,4-dichlorophenyl isocyanate and 0.52 ml (3.70 mmol) of triethylamine. After 30 min the reaction was warmed to room temperature and extracted with aqueous 10% KHSO4/EtOAc (3×). The organic phases were washed with aqueous saturated NaHCO3, 10% NaCl and dried over Na2SO4 to yield after purification by flash silica gel column (EtOAc/n-heptane 1:2 to 3:1) 0.91 g (68%) of the titled compound as white foam. MS: 374.1 (MH+, 2Cl).

1. extractionextracted with aqueous 10% KHSO4/EtOAc (3×)
2. washThe organic phases were washed with aqueous saturated NaHCO3, 10% NaCl
3. dry with materialdried over Na2SO4
4. customto yield
5. customafter purification by flash silica gel column (EtOAc/n-heptane 1:2 to 3:1) 0.91 g (68%) of the titled compound as white foam