1,3-Dichloroacetone → (S)-8-chloro-1-(4-chloromethyl-thiazol-2-yl)-11,12,13,13a-tetrahydro-9H-imidazo[1,5-a]pyrrolo[2,1-c][1,4]benzodiazepin-9-one

Participants

Reaction Steps

A suspension of 6.8 g (0.0204 mol) of (S)-8-chloro-9-oxo-11,12,13,13a-tetrahydro-9H-imidazo[1,5-a]pyrrolo[2,1-c][1,4]-benzodiazepine-thiocarboxamide in 100 ml of dioxan was treated with 2.85 g (0.0224 mol) of 1,3-dichloro-2-propanone and boiled at reflux for 48 hrs. After cooling 30 g of silica gel were added and the mixture was stirred for a further 1 hr. The mixture was concentrated in a water-jet vacuum and dried in a high vacuum. The crude product, adsorbed on silica gel, was applied to a silica gel column equilibrated with ethyl acetate and then eluted with ethyl acetate. There were obtained 4.7 g (58%) of (S)-8-chloro-1-(4-chloromethyl-thiazol-2-yl)-11,12,13,13a-tetrahydro-9H-imidazo[1,5-a]pyrrolo[2,1-c][1,4]benzodiazepin-9-one in the form of white crystals.

Provenance & Evidence