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:
Sep. 02, 1997
Filed:
Dec. 08, 1994
Detlef Kampmann, Gersthofen, DE;
Georg Stuhlmuller, Gablingen, DE;
Hoechst Aktiengesellschaft, , DE;
Abstract
Process for the continuous preparation of 2,2,6,6-tetramethylpiperidine. The reduction of triacetonamine with hydrazine also succeeds continuously by reactive distillation if the hydrazone is first formed and this is continuously transported to the distillation bottoms comprising a high-boiling solvent and an alkali at the base of a distillation column and the resulting 2,2,6,6-tetramethylpiperidine is distilled off as an azeotrope. In this procedure a hydrazine/triacetonamine ratio of 1.5:1 to 2.0:1 is sufficient, in comparison with the conventional synthesis, the product yield being able to be considerably increased (>90%). Moreover, the amounts of alkali and solvent used can be considerably reduced.