Process for the preparation of phosphonic acid dihalides

US3972923A · kind A · utility

Assignee

• Hoechst GmbH · DE

Inventors

• Manfred Finke
• Hans-Jerg Kleiner · Kronberg, DE
• Gerhard Stahler · Frankfurt am Main, DE
• Klaus Dehmer · Kelkheim, DE

Key dates

• Filing date: Nov 13, 1973
• Grant date: Aug 3, 1976
• Expiry date: Nov 13, 1993

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07F9/42
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Process for preparing phosphonic acid dihalides of the formula ##EQU1## wherein R is alkyl of 1 to 18 carbon atoms, cycloalkyl of 4 to 8 carbon atoms, alkenyl of 2 to 18 carbon atoms, phenyl, phenalkyl or alkyl-phenyl of 7 to 8 carbon atoms, phenyl, phenalkyl or alkyl-phenyl of 7 to 8 carbon atoms, all radicals R optionally being substituted by chlorine, bromine, cyano or lower acyloxy, and wherein X is halogen such as 2-chloroethane phosphonic acid dichloride, by reacting phosphonic or thio-phosphonic acids of the formula ##EQU2## wherein Y is oxygen or sulfur, their salts or functional derivatives, with acid halides of the formula EQU (CO).sub.n X.sub.2 (III) wherein X is chlorine or bromine and n is 1 or 2, in the presence of 0.2 - 5% or in the presence of 0.01 to 0.2% by weight of PA1 1. compounds containing at least one tri- to pentavalent nitrogen or phosphorus atom, which in the case of nitrogen is bound with 1 to 4, in the case of phosphorus with at least 3 valences to organic radicals having up to 20 carbon atoms, two of these valences optionally forming a double bond, or PA1 2. mono-di- or tribasic organic or inorganic fully amidated acids or tri- or pentavalent phosphoru…