Process for the preparation of chloroformic acid aryl esters

US4366102A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Gunter Rauchschwalbe · Leverkusen, DE
• Heinz U. Blank · Odenthal, DE
• Karl Mannes · Leverkusen, DE
• Dietmar Mayer · Bensberg, DE

Key dates

• Filing date: May 6, 1981
• Grant date: Dec 28, 1982
• Expiry date: May 6, 2001

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B01J2231/4288
• WIPO field: Chemical engineering
• WIPO sector: Chemistry

Abstract

In a process for the preparation of an aromatic chloroformic acid ester by contacting a phenol and phosgene, the improvement wherein the reaction is carried out in a homogeneous liquid phase at a temperature of 60.degree. to 180.degree. C. in the presence of organic phosphorus compound of the formula EQU R.sup.1 R.sup.2 R.sup.3 PR.sup.4.sub.n X.sub.n in which PA1 R.sup.1, R.sup.2 and R.sup.3 independently of one another represent hydrogen, alkyl, alkenyl, aralkyl, aryl or halogen and two of the said radicals together with the phosphorus atom can form a 5-membered or 6-membered phosphorus-containing saturated or unsaturated heterocyclic radical, PA1 X represents OH, homopolar-bonded halogen or an inorganic or organic acid anion, PA1 R.sup.4 denotes hydrogen or alkyl or, if X denotes halogen, can also denote halogen and n denotes 0 or 1, and in which, furthermore, PA1 R.sup.4 and X together can represent oxygen or sulfur.