MANUFACTURE OF OPTICALLY ACTIVE COMPOUND AND METHOD OF USING IT FOR VITAMIN E PRODUCTION

摘要

Optically active compounds of the formula I IMAGE in which A is a -CH2OR1 group where R1 is hydrogen, lower alkyl, aryl or lower acyl, also an optionally acetalised or acylated formyl group or a carboxyl group, B is an optionally acetalised or acylated formyl group or a group of the formula -COOR2 in which R2 is a lower alkyl radical, and where A and B are always different and where, furthermore, A and B can together be the group CH2-O-CO-, are prepared by hydrogenation of compounds of the formula II IMAGE in the presence of a complex catalyst which is soluble in the reaction mixture and is formed from a rhodium or ruthenium compound and a chiral phosphine or arsine ligand. The optical yields are good. Compounds obtainable in this way are suitable for preparing RRR- alpha - tocopherol.