Hydrochloric Acid → 7-[2-(4-Methyl-3-oxooct-1-enyl)-5-oxocyclopentyl]heptanol

Participants

Reaction Conditions

Reaction Steps

A mixture of 6-(7-hydroxyheptyl)-7-(4-methyl-3-oxooct-1-enyl)-1,4-dioxaspiro[4,4]-nonane (1.0 g.) and hydrochloric acid (25 ml; 1 N) was stirred at 60° C. for 2 hours, cooled to ambient temperature and extracted with diethyl ether. The ether extract was washed with 2 N aqueous sodium carbonate solution and water respectively, then dried over magnesium sulphate. Removal of the solvent under reduced pressure gave a crude product (0.7 g.) which was purified by preparative thin layer chromatography on silica gel, using a mixture of diethyl ether, ethyl acetate and hexane (2:1:1 v/v) as eluant, to give 7-[2-(4-methyl-3-oxooct-1-enyl)-5-oxocyclopentyl]heptanol (0.38 g.), νmax (liquid film) 3450 cm-1, 1730 cm-1, 1690 cm-1, 1660 cm-1, 1380 cm-1, 995 cm-1 ; νmax (ethanol) 230 nm (ε=13,600); Elemental analysis: found: C, 74.9; H 11.0%; C21H36O3 requires C, 74.95; H, 10.8%, N.M.R. (approximately 10% solution in deuterochloroform): Triplets at 3.57δ (J=6 cycles/sec.) and 0.88δ, doublet of doublets at 6.81δ (J=15.5 cycles/sec. and J=7 cycles/sec.), doublets at 6.20δ (J=15.5 cycles/sec.) and 1.11δ (J=7 cycles/sec.), broad singlet 2.0δ.

Provenance & Evidence