Hydrochloric Acid → HCID 54424744, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 1.46 g (0.005 mol) of 3-(4-chlorophenyl)-5,6,7,8-tetrahydro-4H-cyclohept[d]isoxazole-7-carboxylic acid in 20 ml of tetrahydrofuran was added slowly at -70° C. to a solution of lithium diisopropylamide prepared by adding 4.4 ml of a 2.5M solution of n-butyllithium in hexane to 1.11 g (0.011 mol) of diisopropylamine in 20 ml of dry tetrahydrofuran at -70° C. After 15 minutes, 0.78 g of methyl iodide was added and the mixture was allowed to warm to 20° C. The mixture was added to water, acidified with 2N hydrochloric acid and extracted with diethyl ether. The resulting mixture of the cis- and trans-3-(4-chlorophenyl)-5,6,7,8-tetrahydro-8-methyl-4H-cyclohept[d]isoxazole-7-carboxylic acid were separated by a combination of crystallization from acetic acid and chromatography on silica gel using toluene/methanol for the elution. There was obtained 0.4 g of cis-3-(4-chlorophenyl)-5,6,7,8-tetrahydro-8-methyl-4H-cyclohept[ d]isoxazole-7-carboxylic acid of melting point 230°-233° C. (from acetic acid).

Provenance & Evidence