Preparation of .alpha.-tocopherol

US4550182A · kind A · utility

Assignee

• BASF SE

Inventors

• Hansgeorg Ernst · Speyer, DE
• Henning-Peter Gehrken · Lambsheim, DE
• Joachim Paust · Schifferstadt, DE

Key dates

• Filing date: Mar 12, 1984
• Grant date: Oct 29, 1985
• Expiry date: Mar 12, 2004

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D311/72
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process for the preparation of .alpha.-tocopherol of the formula I ##STR1## by reacting a chroman derivative with a C.sub.14 -Grignard reagent using a di-alkali metal tetrahalocuprate catalyst in a Schlosser-Fouquet reaction, wherein a chroman derivative of the general formula II ##STR2## where Y is a leaving group, especially Br, is used and is reacted, at from -70.degree. to 0.degree. C., first with a solution of about 1 equivalent of a Grignard compound of the general formula III EQU X--Mg--R (III) where X is Cl, Br or I and R is straight-chain or branched alkyl of 1 to 14 carbon atoms, preferably methyl, ethyl or ##STR3## and then with a solution of a Grignard reagent of the formula IIIa ##STR4## in an ether solvent and a solution of a di-alkali metal tetrahalocuprate in an ether solvent. The novel process simplifies the preparation of 2RS,4'RS,8'RS-, 2R,4'RS,8'RS- or 2R,4'R,8'R-.alpha.-tocopherol by reacting a chroman structural unit, containing a C.sub.2 side-chain in the 2-position, with the corresponding C.sub.14 -Grignard compound.