Hydrochloric Acid → Diphenylmethylphosphonic acid

Participants

Reaction Steps

Benzhydrylphosphonic acid was prepared as follows. 308.93 g (1.25 moles) of bromodiphenylmethane (Aldrich Chemical Company) and 240.93 g (1.45 moles) of triethyl phosphite (Aldrich Chemical Company) were combined under nitrogen, heated carefully and maintained at 160° C. with removal of bromoethane by-product by distillation over a period of 4 hours. 750 ml of concentrated hydrochloric acid (~12 molar) and 250 ml of distilled water was added to the crude product and the mixture was refluxed under nitrogen for two days (approximately 40 hours). The frothy mixure was allowed to cool and then filtered. The resulting solid was then washed with water, to remove the remaining hydrochloric acid, and then with petrol (b.p. 60°-80° C.), to remove hydrocarbon by products, for example 1,1,2,2-tetraphenylethane. The solid was then dried in a vacuum oven at 120° C. 250.06 g (81% yield) was obtained.

Provenance & Evidence