反应详情

To a solution of 2.5 parts of 2-(2-azido-1-ethoxyethylideneamino)-5-nitrobenzophenone produced in Step (2) in 30 parts by volume of benzene is added with stirring 1.78 parts of triphenylphosphine. The mixture is stirred for further 1.5 hours and the solvent is removed by distillation. The residue is extracted with a mixture of n-hexane and acetone (7:3), and the soluble fraction is purified by means of chromatography employing Silica Gel, whereupon 2-ethoxy-7-nitro-5-phenyl-3H-1,4-benzodiazepine is obtained as pale yellow crystals. Recrystallization from ether-n-hexane gives pale yellow prisms melting at 143°-145° C.

1. customthe solvent is removed by distillation
2. extractionThe residue is extracted with a mixture of n-hexane and acetone (7:3)
3. customthe soluble fraction is purified by means of chromatography