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:
Sep. 14, 1999
Filed:
Oct. 30, 1997
Applicant:
Inventors:
Ian Jeffrey Priestley, Blackley, GB;
James Peter Muxworthy, Huddersfield, GB;
John Heathcote Atherton, Huddersfield, GB;
Martin Lennon, Huddersfield, GB;
Stephen Martin Brown, Huddersfield, GB;
Assignee:
Zeneca Limited, London, GB;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07C / ; C07C / ; C07C / ;
U.S. Cl.
CPC ...
568585 ; 568939 ; 568840 ; 568424 ; 568306 ; 560 21 ; 562434 ; 562435 ; 562438 ;
Abstract
A process for the nitration of an aromatic or heteroaromatic compound with a nitrating agent comprising nitric acid or a mixture of nitric and sulphuric acids, characterised in that nitration is performed in a solvent comprising at least 50% v/v of a C.sub.1 -C.sub.6 alkyl ester of a C.sub.1 -C.sub.4 carboxylic acid. The process is of particular use for the nitration of diphenyl ethers to give compounds which are useful as herbicides or as intermediates in the synthesis of herbicides.