Process for preparing cyclic phosphinic acid esters

Abstract

Process for preparing cyclic phosphinic acid esters of the formula (I) ##STR1## wherein R.sub.1 is an alkyl radical having up to 18 carbon atoms or a phenyl radical being optionally substituted by alkyl, halogen or alkylated amino groups, R.sub.2 stands for a hydrogen atom or has the same meaning as R.sub.1 and n is 1 or 2, which comprises reacting phosphinic acid monoesters of the formula (II) ##STR2## wherein R.sub.3 is an alkyl radical having up to 8 carbon atoms optionally substituted by chlorine atoms and R.sub.1 has the meaning given above, with an alkenol of the formula (III) ##STR3## wherein R.sub.2 and n have the aforesaid meaning, in the presence of catalytic quantities of free radical forming agents, splitting off the alcohol of formula (IV) r.sub.3 oh (iv) simultaneously or subsequently and separating the reaction products, preferably by distillation.

Dependencies are inferred from the claim text.