1: 1-(3,4-dichloro-phenyl)-3-aza-bicyclo[3.1.0]hexane-2,4-dione With sodium hydride in N,N-dimethyl-formamide T=20°C; 0.333333 h; 2: 1-bromo-butane in N,N-dimethyl-formamide T=20°C; 24 h;

1: 1-(3,4-dichloro-phenyl)-3-aza-bicyclo[3.1.0]hexane-2,4-dione With sodium hydride in N,N-dimethyl-formamide T=20°C; 0.333333 h; 2: 1-bromo-butane in N,N-dimethyl-formamide T=20°C; 24 h; 3: With water in N,N-dimethyl-formamide