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:
Dec. 11, 1979
Filed:
May. 02, 1978
Applicant:
Inventors:
Fritz Englaender, Bonn-Bad Godesberg, DE;
Fritz Robert Kappler, Troisdorf, DE;
Assignee:
Dynamit Nobel Aktiengesellschaft, Troisdorf, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C07D / ;
U.S. Cl.
CPC ...
2603 / ;
Abstract
An improvement in a process for preparing phthalide by reacting chlorophthalide with hydrogen in the presence of a catalyst at a temperature between 50.degree. and 350.degree. C., the improvement residing in carrying out the process in the absence of a hydrogen chloride acceptor, flowing the chlorophthalide continuously in fluid form through a solid catalyst bed in a reactor, passing the hydrogen through in such an excess so as to sweep off the hydrogen chloride formed and withdrawing phthalide in fluid form.