Tetrahydrofuran → Methyl [2-(3,5-dimethoxyphenyl)cyclohexylidene]acetate

Participants

Reaction Conditions

Reaction Steps

To a suspension of 3.9 g. (0.081 mole) 50% sodium hydride in 500 ml. anhydrous tetrahydrofuran (THF) was added dropwise at room temperature a solution of 16.2 g. (0.089 mole) trimethylphosphonoacetate in 50 ml. THF and the mixture stirred for 15 minutes. A solution of 17.4 g. (0.074 mole) 2-(3,5-dimethoxyphenyl)cyclohexanone in 100 ml. THF was added in portions after which the mixture was heated at 70° C. for three hours and cooled to 0° C. Glacial acetic acid, 5.4 g., was added and the resulting mixture diluted with water and extracted with ethyl acetate. The extracts were dried (Na2SO4) and evaporated to give 22 g. of crude product which was crystallized from isopropyl ether; 20.4 g., M.P. 80°-81° C. 1H-NMR (CDCl3) ppm (delta): 3.60 (s, 3H, COOCH3), 3.80 (s, 6H, OCH3), 5.20 (s, 1H, olefin), 6.34 (s, 3H, aromatic). Mass spectrum, exact mass for C17H24O4 : 292.3783. Found: 292.1658.

Provenance & Evidence