2,5-bis(1,1-dialkoxy-2-propyl)-2,5-dihydrofurans, the preparation thereof and the use thereof for the preparation of carotenoids

US5382732A · kind A · utility

Assignee

• BASF SE

Inventors

• Juergen Frank · Ludwigshafen, DE
• Udo Rheude · Otterstadt, DE
• Bernhard Schulz · Schwetzingen, DE
• Joachim Paust · Schifferstadt, DE
• Eckhard Hickmann · Schifferstadt, DE

Key dates

• Filing date: May 27, 1993
• Grant date: Jan 17, 1995
• Expiry date: May 27, 2013

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07D307/28
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process of preparing symmetric C.sub.40 -carotenoids by reacting a C.sub.15 -triphenylphosphonium salt of the formula ##STR1## and a 2,5-bis(1,1-dialkoxy-2-propyl)-2,5-dihydrofuran to form a reaction product containing a diacetyl and a triphenylphosphonium salt, adding a strong base to the reaction product to convert the triphenylphosphonium salt to a carbenium ion, hydrolyzing the diacetyl to a dialdehyde, subjecting the dialdehyde and the carbenium ion to a Wittig reaction to prepare a Wittig reaction product, and converting the Wittig reaction product to the C.sub.40 -carotenoid by acid treatment.