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:
Nov. 09, 1993
Filed:
Dec. 18, 1989
Isoo Shimizu, Yokohama, JP;
Yasuo Matsumura, Yokohama, JP;
Yuichi Tokumoto, Yokohama, JP;
Kazumichi Uchida, Yokohama, JP;
Nippon Petrochemicals Co., Ltd., Tokyo, JP;
Abstract
A method for preparing .alpha.-(4-isobutylphenyl)propionic acid or its precursor is here disclosed which comprises a step (I) of dehydrogenating p-isobutylethylbenzene in a gaseous phase in the presence of a dehydrogenating metal catalyst to form p-isobutylstyrene and at least one unsaturated hydrocarbon compound selected from a group A defined in Claim 1; a step (II) of reacting p-isobutylstyrene obtained in the step (I) with carbon monoxide and hydrogen or with carbon monoxide and water or a lower alcohol in the presence of a transition metal complex carbonylating catalyst to form .alpha.-(4-isobutylphenyl)propionic acid or its precursor; and a step (III) of hydrogenating at least one unsaturated hydrocarbon compound selected from the group A obtained in the dehydrogenation step (I) to form p-isobutylethylbenzene, and recycling the thus formed p-isobutylethylbenzene through the step (I) as the raw material of the step (I).