Water → Methyl 1-Acetyl-4-(4-hydroxybenzenesulfonyl)-2,3,4,5-tetrahydro-1H-[1,4]benzodiazepine-3-carboxylate

Participants

Reaction Steps

To a 0° C. solution of methyl 1-acetyl-4-(4-methoxybenzenesulfonyl)-2,3,4,5-tetrahydro-1H-[1,4]benzodiazepine-3-carboxylate (9.8 g, 23.42 mmol) in methylene chloride (50 ml) was added, dropwise, a 1.0 molar solution of boron tribromide (51.52 ml, 51.52 mmol) in methylene chloride and the mixture was stirred overnight at room temperature. Ice and water were added to the reaction mixture and the insolubles filtered off. The filtrate was diluted with methylene chloride and water. The organic layer was separated, washed with saturated sodium chloride and dried over anhydrous sodium sulfate. The solvent was removed in vacuo to give a crude product, which was purified by chromatography on silica gel (hexane:ethyl acetate (I:1)) to give 3.2 g of product as a white foam.

Provenance & Evidence