Hydrochloric Acid → (E)-4-benzylthio-3-[2-(2,3-dihydro-1-methyl-1H-1,4-benzodiazepin-5-yl)vinyl]aniline dihydrochloride

Participants

Reaction Conditions

Reaction Steps

To 215 mg (0.50 mmol) of (E)-5-(2-benzylthio-5-nitrostyryl)-2,3-dihydro-1-methyl-1H-1,4-benzodiazepine dihydrochloride (prepared as described in Example 15) in 8 ml of tetrahydrofuran and 8 ml of ethanol was added 380 mg (0.90 mmol) of tin (II) chloride and 0.48 ml of concentrated hydrochloric acid. The mixture was heated at 60° C. for 7 hours. The solution was reduced to half volume and partitioned between 50 ml of saturated sodium hydrogen carbonate solution and 100 ml and 50 ml of dichloromethane. The combined organic phases were dried (magnesium sulphate), filtered and evaporated. The residue was purified by column chromatography eluting with 2-5% methanol/dichloromethane and treated with 0.30 ml of 4M hydrogen chloride in dioxan. The solvent was evaporated and the residue was recrystallised from methanol/ether to give 46 mg of (E)-4-benzylthio-3-[2-(2,3-dihydro-1-methyl-1H-1,4-benzodiazepin-5-yl)vinyl]aniline dihydrochloride as dark red crystals; MS: m/e 400 [M+H]+.

Provenance & Evidence