Thiophosphoric acid and thiophosphonic acid halide prodn. - by reacting phosphoric or phosphonic acid halide with phosphorus tri:chloride and sulphur

摘要

In the prodn. of thiophosphoric and thiophosphonic acid halides of formula R-P(=S)XR1 (I) (where R is 1-20C alkyl, 2-20C alkenyl, 7-12C aralkyl or 6-10C aryl, opt. mono-, di- or trisubstd, by Cl, Br, 1-4C alkyl or 1-4C alkoxy; X is halogen1 and R1 is R or X) by reacting a halide of formula R. P(=O)XR1 (II) with PSCl3 at 140-250 (150-200) degrees C at approximately atmospheric pressure, with continuous removal of resulting POCl3 by distn., (a) PCl3 and sulphur are used instead of PSCl3; (b) the reaction is carried out at moderately elevated pressure; and (c) the continuous removal of POCl3 by distn. is opt. omitted. (I) are intermediates for plant protection agents, selective extraction agents and lubricant additives. Process avoids use of PSCl3, and gives shortened reaction times.