NUCLEOPHILIC SUBSTITUTION REACTIONS ON ANTIMONY(III) 0,0-DISUBSTITUTED PHOSPHORODITHIOATES

Abstract

Antimony(III) tris(0,0-diisobutyl phosphorodithioate), 1 (R = i-Bu) has been found to undergo a nucleophilic displacement reaction with sodium 1-propanethiolate to give antimony(III) tris-(1-propanethiolate), 4, and sodium 0,0-diisobutyl phosphorodithioate (8, R = i-Bu). Reaction of 1 (R = i-Bu) with phenyllithium gave triphenylstibine and lithium 0,0-diisobutyl phosphorodithioate. Similar reactions of various compounds of type 1 with the sodium salts of carboxylic acids and with the sodium salt of pyrrole were also found to occur. Furthermore, antimony tris(0,0-diisobutyl phosphorodithioate), 1 (R = i-Bu), was found to undergo solvolysis with n-propyl mercaptan to give 4 and 0,0-diisobutyl phosphorodithioic acid 5. Compounds of type 1 are used as passivating agents in petroleum refining, and reactions of the types described for 1 with n-propyl mercaptan and with the salts of carboxylic acids probably occur when “Phil-Ad CA” is added to the feedstock of a fluid catalytic cracking unit.