Process for the preparation of (R)-2-alkyl-3-phenyl-1-propanols

US6881868B2 · kind B2 · utility

Assignee

• Speedel Pharma AG · CH

Inventors

• Stefan Stutz · Basel, CH
• Peter Herold · Allschwil, CH
• Felix Spindler · Starrkirch-Wil, CH
• Walter Weissensteiner · Wien, AT
• Thomas Sturm · Erie, US

Key dates

• Filing date: Jun 26, 2001
• Grant date: Apr 19, 2005
• Expiry date: Jun 26, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C69/734
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

Compounds of formula (I), wherein R1 and R2 are, independently of one another, H,C1-C6alkyl, C1-C6halogenalkyl, C1-C6alkoxyl, C1-C6alkoxy-C1-C6alkyl, or C1-C6alkoxy-C1-C6alkyloxy, and R3 is C1-C6alkyl, are obtainable in high yiedls by stereoselective addition of R3-substituted propionic acid esters to R1- and R2-substituted benzaldehydes of formula R—CHO to form corresponding 3-R-3-hydroxy-2-R3-propionic acid esters, conversion of the OH group to a leaving group, subsequent regioselective elimination to form 3-R-2-R3-propenic acid esters, and reduction to corresponding 3-R-2-R3-allyl alcohols and their enantioselective hydrogenation, wherein R is (a).