Ethyl cycloheptanecarboxylate → Ethyl 1-(2,3-dimethoxybenzyl)cycloheptane Carboxylate

Participants

Reaction Conditions

Reaction Steps

To a stirred solution of ethyl cycloheptane carboxylate (14 g, 82.4 mmol, prepared by esterification of the acid, which was obtained from Aldrich, by refluxing in ethanol in the presence of an acid catalyst), in 600 mL anhydrous THF cooled to -78° C. was added 60 mL of 1.5M LDA (monotetrahydrofuran in hexane, Aldrich) via syringe. The resulting light yellow reaction solution was stirred at -78° C. for 45 min and the benzyl bromide (from step A above) was added (19 g dissolved in 75 mL of THF, 82.4 mmol). The reaction was stirred at -78° C. for 4 hours, then it was quenched by addition of sat'd. NH4Cl, water and ether. The layers were separated, and the organic layer was washed with 1M HCl, water, and brine. The organic layer was dried over MgSO4, filtered, and evaporated to yield a light amber oil (28 g) which was used without further purification.

Provenance & Evidence