Process for the preparation of neutral phosphorous acid aryl esters

US4356129A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Uwe Hucks · Alpen, DE
• Erhard Tresper · Krefeld, DE
• Claus Wulff · Krefeld, DE

Key dates

• Filing date: Dec 4, 1980
• Grant date: Oct 26, 1982
• Expiry date: Dec 4, 2000

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07F9/145
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of a neutal phosphorous acid aryl ester of the general formula ##STR1## wherein a phosphorus trihalide, phosphorus acid monoester dihalide or phosphorous acid diester halide is reacted with a hydroxyaryl compound wherein an excess of hydroxyaryl compound and an excess of aqueous alkali metal hydroxide solution or suspension or alkaline earth metal hydroxide solution or suspension are employed, relative to the phosphorus halide compound, an inert water immiscible organic solvent and/or diluent is employed in an amount such that 5 to 50% strength solution of the neutral phosphorous acid aryl ester is formed and after the reaction, the organic phase is separated off and the phosphorous acid aryl ester formed is isolated by removing the solvent and/or diluent.