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:
Jul. 06, 1999
Filed:
Sep. 29, 1997
Hans Hilpert, Reinach, CH;
Erich Widmer, Munchenstein, CH;
Roche Vitamins Inc., Parsippany, NJ (US);
Abstract
A process for the manufacture of an optionally protected 4,8,8-trimethyl-1-oxaspiro�2.5!oct-4-en-6-ol (I) starting from protected 4-hydroxy-2,6,6-trimethyl-2-cyclohexen-1-one (II) comprises reacting the protected compound (II) with dihalomethyllithium and, if desired, cleaving off the protecting group from the thus-obtained protected 4,8,8-trimethyl-1-oxaspiro�2.5!oct-4-en-6-ol. The dihalomethyllithium can be produced in situ by reacting a dihalomethane with a lower alkyllithium in the presence of the compound of formula II. Preferably, protected (S)-4-hydroxy-2,6,6-trimethyl-2-cyclohexen-1-one is converted into protected (3S,6S)-4,8,8-trimethyl-1-oxaspiro�2.5!oct-4-en-6-ol in this manner. Both the starting material (II) and the end product (I) of the process in accordance with the invention are known, valuable intermediates for the manufacture of carotenoids.