Ethanol → Phosphonic acid, (dichloromethyl)-, diethyl ester

Participants

Reaction Conditions

Reaction Steps

153.5 g (2.26 mol) of sodium ethylate in 800 ml of ethanol were added dropwise to a solution of 227.5 g (1.13 mol) of dichloromethane-phosphonic acid dichloride in 800 ml of toluene at 5°-10° C. The reaction mixture was subsequently stirred at 20° C. for five hours. It was then filtered, the filtrate was concentrated and the residue was subjected to fractional distillation. 195 g (78% of theory) of dichloromethane-phosphonic acid diethyl ester were obtained in the form of a colorless oil of boiling point 84° C./1 mbar. ##STR10## A suspension of 24.6 g (0.22 mol) of potassium tert.-butylate in 20 ml of dimethylformamide was added dropwise to a mixture of 48 g (0.22 mol) of dichloromethane-phosphonic acid diethyl ester and 34 g (0.2 mol) of 3-formyl-2,2-dimethyl-cyclopropane-1-carboxylic acid ethyl ester in 200 ml of tetrahydrofuran at -15° C. When the addition had ended, the reaction mixture was warmed to 20° C. and was stirred at this temperature for two hours.

Provenance & Evidence