4-tert-Butylcyclohexanone → (4-tert-Butylcyclohexylidene)acetic acid methyl ester

Participants

Reaction Steps

4-tert-Butylcyclohexanone (8.62 g, 56 mmol) was dissolved in toluene (200 ml). Methoxycarbonylmethylenetriphenylphosphorane (56.1 g, 168 mmol) was added with stirring and the reaction mixture was heated under reflux for 3 days. The solvent was removed in vacuo. The residue was dissolved in hot hexanes (100 ml) and cooled to room temperature. The precipitate was filtered off and the filtrate was evaporated in vacuo to afford a yellow oil which was then purified by chromatography (silica gel, hexane/ethyl acetate, 2:1 as eluant) to give the title compound as an oil (10.78g, 92%). 1H-NMR; δ (CDCl3) 5.60 (1H, s), 3.87 (1H, m), 3.69 (3H, s), 2.38-2.10 (2H, m), 2.03-1.77 (3H, m), 1.36-1.02 (3H, m) and 0.87 (9H, s).

Provenance & Evidence