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:
Oct. 21, 1997
Filed:
Feb. 13, 1996
Frederic Brunner, Chezard, CH;
Ciba-Geigy Corporation, Tarrytown, NY (US);
Abstract
A process is described for preparing diphenylamines of the formula ##STR1## by oxybromination of a phenol ether compound using elemental bromine in the presence of hydrogen peroxide and of a catalyst to give a brominated phenol ether compound which is subsequently reacted with a formanilide compound to give the compound of the formula (1). The oxybromination reaction is a regioselective, environmentally friendly and cost-efffective method of preparing brominated aromatic compounds. The diphenylamines of the formula (1) are industrially useful intermediates for the production, for example of dyes, and in particular of color formers of the fluoran type for pressure- or heat-sensitive recording systems.