摘要 |
Compounds of formula I <IMAGE> (I) wherein R1 denotes identical or different radicals and is linear or branched C1-C12alkyl, unsubstituted C5-C6cycloalkyl or C5-C6cycloalkyl which is substituted by C1-C4alkyl or C1-C4alkoxy, or is phenyl or benzyl, or both substituents R1 of a group (R1)2P are o,o'-diphenylene, R2 is hydrogen, linear or branched C1-C12alkyl, phenyl or benzyl, R3 is C1-C12alkylene, R4 is C2-C18alkylene, phenylene or benzylene, and R5 is C1-C6alkyl or phenyl, can be applied to solid carriers, such as silica gel or aerosils, and complexed with rhodium or iridium compounds. These materials are heterogeneous and separable catalysts for the asymmetrical hydrogenation of prochiral compounds containing carbon double bonds or carbon/hetero atom double bonds, for example ketones and imines.
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