Dichloromethane → HCID 178445815, compound

Participants

Reaction Steps

A mixture of 200 mg of trans-4-(1E-butenyl)cyclohexanecarboxylic acid, 272.4 mg of dicyclohexylcarbodimide, 13.4 mg of 4-(dimethylamino)pyridine, 169.7 mg of trans-4-(1E-butenyl)cyclohexanol and 4 ml of methylene chloride was stirred at room temperature for 21 hours while gassing with argon. Subsequently, the heterogeneous reaction mixture was diluted with 10 ml of hexane and filtered (rinsing with hexane). The concentrated filtrate was taken up in 30 ml of hexane and the solution was washed in each case once with 30 ml of 5 percent hydrochloric acid, 30 ml of saturated sodium hydrogen carbonate solution and 30 ml of saturated sodium chloride solution, dried over magnesium sulphate and concentrated. Low-pressure chromatography (0.5 bar) of the colourless oil (450 mg) on silica gel with ethyl acetate/petroleum ether (vol. 1:99) gave 280 mg (80.1%) of trans-4-(1E-butenyl)cyclohexanecarboxylic acid trans-4-(1E-butenyl)cyclohexyl ester as colourless crystals. Recrystallization from 15 ml of methanol at - 20° C. gave 223 mg of ester as colourless needles with melting point (C-N) 46.3° C. and cl.p. (N-I) 58.7° C.

Provenance & Evidence