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:
Aug. 25, 1981
Filed:
May. 19, 1980
Russell M Bimber, Painesville, OH (US);
Russell Buchman, Madison, OH (US);
Michael F DePompei, Mentor, OH (US);
Larry J Powers, Madison, OH (US);
Diamond Shamrock Corporation, Dallas, TX (US);
Abstract
Valuable pyridazinone intermediates to pharmaceutically useful compounds can be prepared in surprisingly high yields by the reaction of the corresponding monohydrazone with diketene, preferably in the presence of a basic catalyst. In an especially preferred embodiment, p,p'-dichlorobenzil monohydrazone and diketene are reacted in a xylene solvent in the presence of triethylamine to afford 4-acetyl-5,6-bis(p-chlorophenyl)-2H-pyridazin-3-one, which can then be reacted with ethylene carbonate in the presence of potassium carbonate to afford the antihypertensive agent, 4-acetyl-5,6-bis(p-chlorophenyl)-2-(2'-hydroxyethyl)-2H-pyridazine-3-one.