| abstract |
Compounds of formula (I), wherein R 1 and R 2 are, independently of one another, H,C 1 -C 6 alkyl, C 1 -C 6 halogenalkyl, C 1 -C 6 alkoxyl, C 1 -C 6 alkoxy-C 1 -C 6 alkyl, or C 1 -C 6 alkoxy-C 1 -C 6 alkyloxy, and R 3 is C 1 -C 6 alkyl, are obtainable in high yiedls by stereoselective addition of R 3 -substituted propionic acid esters to R 1 - and R 2 -substituted benzaldehydes of formula R—CHO to form corresponding 3-R-3-hydroxy-2-R 3 -propionic acid esters, conversion of the OH group to a leaving group, subsequent regioselective elimination to form 3-R-2-R 3 -propenic acid esters, and reduction to corresponding 3-R-2-R 3 -allyl alcohols and their enantioselective hydrogenation, wherein R is (a). |