3-(1-hydroxy-ethyl)-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylic acid methyl ester → Methyl 3-acetyl-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylate

Participants

Reaction Steps

Reflux a mixture of 3-(1-Hydroxy-ethyl)-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylic acid methyl ester (3.2 g, 0.0141 mol) and manganese dioxide (10.8 g, 0.124 mol) in dichloromethane for 2 hours. Filter the hot reaction mixture solution and concentrate the filtration under vacuum. Purify the residue by silica gel chromatograph (eluting with 2% to 10% ethyl acetate in petroleum ether) to give 3-acetyl-5,6-dihydro-4H-cyclopenta[c]thiophene-1-carboxylic acid methyl ester as white solid (3.0 g, 13.39 mmol, 94.5%). 1H NMR (CDCl3, 400 MHz): δ 3.88 (s, 3H), 2.96 (m, 4H), 2.50 (s, 3H), 2.45 (m, 2H).

Provenance & Evidence