The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 18, 1978
Filed:
Sep. 28, 1976
Applicant:
Inventors:
Gunther Semler, Kelkheim, Taunus, DT;
Georg Schaeffer, Hofheim, Taunus, DT;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt am Main, DT;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ;
U.S. Cl.
CPC ...
260463 ;
Abstract
A process for the preparation of chloroformic acid aryl-esters and cyclic carbonates of aryl compounds containing at least two phenolic hydroxy groups wherein aromatic compounds containing one or more hydroxy groups linked to an aromatic nucleus, are reacted with phosgene in the presence of catalytic amounts of N,N-disubstituted acid amide either under pressure or without pressure while removing the hydrogen chloride continuously from the reaction mixture. This improved process results in almost quantitative or very high yields of pure products and avoids problems such as disposal of waste water.