Syntheses of dialkyl trichloromethylphosphonates and their properties for additives

Abstract

AbstractNine dialkyl trichloromethylphosphonates (TCMPs) were synthesized by the Arbusov reaction from the corresponding trialkyl phosphite and carbon tetrachloride. Some characteristics of these compounds were studied. The alkyl groups contained from 2 to 18 even carbon atoms. The reaction of triethyl phosphite and carbon tetrachloride was completed in about 4 hr under an indoor natural light. However, in the preparation of the lower dialkyl TCMPs the mixture of trialkyl phosphite and carbon tetrachloride was refluxed for 8 hr. With alkyl groups higher than decyl, a reaction time of 8 hr was insufficient. Utilization of these dialkyl TCMPs was discussed. These compounds were shown to be effective chelating, antistatic and flame resistant additives in a formulation of polyvinyl chloride. Moreover, they were found to be very excellent extreme pressure additives for lubricating oil; especially the dibutyl TCMP which was extremely effective at concentrations as low as 0.25%.