Sodium Thiosulfate → Octahydro-3H-2-benzopyran-3-one

Participants

Reaction Conditions

Reaction Steps

To a stirred mixture of 3.16 g (23 mmol) of (3a alpha, 7a alpha)-octahydro-2H-inden-2-one, 17.3 g (207 mmol) of NaHCO3 and 300 mL of dichloromethane was added 9.29 g of 85% m. chloroperoxybenzoic acid in small portions over 15 min. The reaction mixture was stirred for 17 h at 20° C., then 200 mL of 10% aqueous Na2S2O3 was added and, after 15 min, the organic phase was separated. Extraction of the aqueous portion with 2×100 mL of dichloromethane, washing of the combined organic solutions with 10% Na2CO3 and concentration of the dried (MgSO4) solutions under vacuum gave 3.51 g (95%) of racemic (4a alpha, 8a alpha)-octahydro-3H-2-benzopyran-3-one. TLC Rf 0.40 (SiO2, ethyl ether, iodine-brown).

Provenance & Evidence