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. 02, 1990
Filed:
Nov. 13, 1987
Applicant:
Inventor:
Young S Lo, Richmond, VA (US);
Assignee:
A. H. Robins Company, Inc., Richmond, VA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ; C07D / ;
U.S. Cl.
CPC ...
546298 ; 546296 ; 546345 ;
Abstract
A process for the preparation of 5-halo-2-hydroxynicotinic acids having the formula: ##STR1## wherein X is chlorine or bromine, Y and Z are selected from hydrogen, loweralkyl or loweralkyl, is described wherein a corresponding 2-hydroxynicotinic acid is halogenated with alkali-metal hypohalite in a strongly alkaline solution pH 12 and above. Certain aspects of the isolation of the product are directed to avoiding replacement of the carboxy group with halogen.