Ethyl chloroformate → 1,3-Dimethyl-4-pyrrolidinoacetyl-1,4,9,10-tetrahydropyrrolo[3,2-b][1,5]benzodiazepin-10-one

Participants

Reaction Conditions

Reaction Steps

1.1 g of ethyl chloroformate are added dropwise at 0° C. to a suspension of 1.29 g of pyrrolidin-1-ylacetic acid in 20 ml of tetrahydrofuran. 2.28 g of 1,3-dimethyl-1,4,9,10-tetrahydropyrrolo[3,2-b][1,5]benzodiazepin-10-one are added to the obtained suspension. The mixture is stirred 1 hour at 0° C. and a further 4 hours at room temperature. It is then poured onto 160 ml of 2 N sodium hydroxide solution and extracted with toluene. The organic phase is concentrated to dryness. The residue is chromatographed over a silica gel column by means of a mixture of dioxane/methanol (1:1) to yield 2.1 g of the title compound of m.p. 210° to 212° C. (from isopropanol).

Provenance & Evidence