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:
Jan. 22, 1991
Filed:
Aug. 15, 1989
Applicant:
Inventor:
Hartmut Fischer, Hofheim am Taunus, DE;
Assignee:
Hoechst Aktiengesellschaft, Frankfurt, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
548305 ;
Abstract
A process for the preparation of cyclic urea derivatives of the formula ##STR1## in which R.sup.1 and R.sup.2 are equal or different and represent hydrogen, alkyl having from 1 to 6 carbon atoms or alkoxy having from 1 to 3 carbon atoms, which comprises reacting a 1,2-diaminobenzene of the formula ##STR2## in which R.sup.1 and R.sup.2 have the meaning indicated above are reacted with carbon dioxide in the presence of water under superatmospheric pressure at a temperature of at least 120.degree. C.