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. 14, 1999
Filed:
Mar. 08, 1999
Manfred Kaufhold, Marl, DE;
Wolfgang Kleemiss, Haltern, DE;
Udo Jegelka, Recklinghausen, DE;
Michael Korell, Bochum, DE;
Huels Aktiengesellschaft, Marl, DE;
Abstract
Cyclopropyl alkyl ketones are separated from 3-acyltetrahydrofuran-2-ones by adding an alcohol, water or a water/alcohol mixture to a reaction product containing C.sub.1-4 -alkyl cyclopropyl ketone and 4,5-dihydro-2-alkylfuran by-product and an acid catalyst and reacting the by-product with the added alcohol, water of water/alcohol mixture before, during or after distilling said reaction product; and effectively separating C.sub.1 -.sub.4 -alkyl cyclopropyl ketone from reaction by-products. In the preparation of cyclopropyl alkyl ketones from 3-acyltetrahydrofuran-2-ones very reactive 4,5-dihydro-2-alkylfurans are also produced. By reacting such compounds with nucleophilic compounds, such as alcohols or water, before, during or after distillation of the reaction products, it is possible reliably to separate off the 4,5-dihydro-2-alkylfurans as high-boiling addition compounds. The offgas which is produced in the production process for cyclopropyl alkyl ketones can be simply and reliably purified by reactive washing. The byproducts, which are difficult to handle for a production process, can thus be reliably eliminated.