m-Chloroperbenzoic acid → HCID 70284007, compound

Participants

Reaction Steps

A solution of m-chloroperoxybenzoic acid (55% purity; 15.2 g) in chloroform (300 ml) was added dropwise over 2.5 hours to a stirred, ice-cold solution of 1-(4-methoxyphenylthio)-4-phenoxybut-2-yne(13.7 g) in chloroform (125 ml), then the mixture was stirred at ambient temperature for 18 hours and filtered. The filtrate was washed with 5% sodium carbonate solution (3×150 ml) and water (3×100 ml), then dried (MgSO4) and filtered. The filtrate was heated under nitrogen at an external temperature of 80°-85° C. for 6 hours, allowed to stand at ambient temperature for 18 hours, heated at an external temperature of 80°-85° C. for a further 1.5 hours, then allowed to cool. The solvent was removed in vacuo, the residue was dissolved in dichloromethane (250 ml), and the solution was shaken vigorously for a few seconds with 5M aqueous sodium hydroxide solution (150 ml). The organic solution was separated, washed with water (2×150 ml), dried (MgSO4), and the solvent removed in vacuo. The residue was purified by flash chromatography over silica using 12.5-25% mixtures of ethyl acetate and petroleum ether (b.p. 60°-80° C.) as eluants. Appropriate fractions were combined, and the solvents removed in vacuo to leave 1-(5-methoxy-2,3-dihydrobenzo[b]thiophen-3-yl)-2-phenoxyethanone as a gum (4.5 g).

Provenance & Evidence