2-Pyrrolidone → Rilmakalim

Participants

Reaction Steps

A solution of 6.3 g (0.02 mole) of 3,4-dihydro-2,2-di-methyl-3,4-epoxy-6-phenylsulfonyl-2H-benzo[b]pyran in 20 ml of DMSO is added dropwise, at 20°, to a suspension of 0.6 g (0.02 mole) of 80% NaH in 10 ml of DMSO. Then 2.3 ml (0.03 mole) of 2-pyrrolidinone are added, and the mixture is stirred at 45° for one hour. After it has stood at 20° overnight it is introduced into ice-water. The precipitate is filtered off with suction, washed to neutrality, dried and chromatographed on silica gel with methylene chloride/methanol 19:1. 30 ml fractions are collected. Fractions 12-22 are concentrated, and the residue is recrystallized from acetonitrile.

Provenance & Evidence