Lawesson's reagent → 1-[4-(1-Hexahydroazepinyl)benzenesulphonyl]-2-pyrrolidinethione

Participants

Reaction Steps

A mixture comprising 5 g of 1-[4-(1-hexahydroazepinyl)benzenesulphonyl]-2-pyrrolidinone, prepared as in Example 18 of the European Patent Application published under No. 0,033,578, and 3.13 g of Lawesson reagent (or 2,4-bis(4-methoxyphenyl)-1,3,2,4-dithiadiphosphetane in 100 cm3 of dimethoxyethane is heated to reflux for 3 hours. The mixture is allowed to return to room temperature and is evaporated to dryness, and the residue is chromatographed on silica (eluant: benzene). 2 g of product are recovered. M.p. 168°-170° C. After crystallization in methanol, 1.5 g of expected product are obtained. M.p. 172°-173° C.

Provenance & Evidence