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