Patent ID: 8378157

Claim:
A process for the preparation of a bis(fluoroalkyl)phosphinyl chloride or a fluoroalkylphosphonyl dichloride which comprises reacting: the corresponding bis(fluoroalkyl)phosphinic acid of the formula I R 1 R 2 P(═O)OH I, or a salt thereof, where R 1 and R 2 each stand, independently of one another, for straight-chain or branched alkyl groups C n F 2n+1−y H y , where n denotes 1-12 and y denotes 0-5, but where y denotes 0, 1 or 2 when n =1 or 2, or the corresponding fluoroalkylphosphonic acid of the formula II R 1 P(═O)(OH) 2 II, or a salt thereof, where R 1 is as defined above, with an aryltetrachlorophosphorane as chlorinating agent, wherein the reaction is carried out at a temperature between −20° C. and 200° C.