Process for preparing phosphinic esters

US6090968A · kind A · utility

Assignee

• Clariant Corporation · DE

Inventors

• Sebastian Hörold · Lechenich, DE
• Norbert Weferling · Hürth, DE
• Heinz-Peter Breuer · Hürth, DE

Key dates

• Filing date: Jun 29, 1999
• Grant date: Jul 18, 2000
• Expiry date: Jun 29, 2019

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08K5/5313
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for preparing phosphinic esters which comprises PA1 a) reacting elemental yellow phosphorus with alkyl halides in the presence of alkali metal hydroxide or alkaline earth metal hydroxide to form a mixture which comprises as main constituents the alkali metal salts and/or alkaline earth metal salts of alkylphosphonous acid, phosphorous acid and hypophosphorous acid PA1 b) removing the alkylphosphonous acid from the mixture obtained as described in a), PA1 c) esterifying the alkylphosphonous acid, PA1 d) adding the resultant ester of the alkylphosphonous acid to a compound having at least one C.dbd.C double bond. The invention likewise relates to the use of the phosphinic esters prepared by this process inter alia as flame retardants and as precursor for further syntheses.