Lithium Hydroxide → 6-(1,3-Dihydro-6-hydroxy-7-methyl-3-oxo-4-p-toluenesulfonyloxyisobenzofuran-5-yl)-4-methyl-4-hexenoic acid

Participants

Reaction Steps

A solution of methyl (E) 6-(1,3-dihydro-7-methyl-3-oxo-4-p-toluenesulfonyloxy-6-vinylisobenzofuran-5-yl)-4-methyl-4-hexenoate (0.37 g) and lithium hydroxide (0.4 g) in methanol (6 ml) and water (6 ml) was heated at 62° C. for 15 hours. The reaction was acidified with aqueous sodium hydrogen sulfate and extracted with ethyl acetate. The extract was dried and evaporated and the residue chromatographed on silica gel, eluting with ethyl acetate/hexane/acetic acid to give (E) 6-(1,3-dihydro-4-hydroxy-7-methyl -3-oxo-6-vinylisobenzofuran-5-yl)-4-methyl-4-hexenoic acid, m.p. 148°-149° C. (tert-butylmethyl ether/hexane).

Provenance & Evidence