Asymmetric hydrogenation of , -unsaturated phosphonates with Rh-BisP* and Rh-MiniPHOS catalysts: Scope and mechanism of the reaction
نویسندگان
چکیده
Optically active 1,2-bis(alkylmethylphosphino)ethanes and bis(alkylmethylphosphino)methanes are unique diphosphine ligands combining the simple molecular structure and P-stereogenic asymmetric environment. This work shows that these ligands exhibit excellent enantioselectivity in rhodium-catalyzed asymmetric hydrogenation of , -unsaturated phosphonic acid derivatives. The enantioselective hydrogenation mechanism elucidated by NMR study is also described.
منابع مشابه
New P-chirogenic diphosphines and their use in catalytic asymmetric reactions*
Enantiomerically pure (S,S)-1,2-bis[(o-alkylphenyl)phenylphosphino]ethanes (o-alkylphenyl = o-methylphenyl, o-ethylphenyl, o-isopropylphenyl, 5',6',7',8'-tetrahydronaphthyl), (S,S)-1,2-bis(alkyl-methylphosphino)ethanes (alkyl = t-butyl, 1-adamantyl, 1-methylcyclo-hexyl, 1,1-diethylpropyl, cyclopentyl, cyclohexyl) (abbreviated as BisP*), and (R,R)-1,1-bis(alkylmethylphosphino)methanes (alkyl = i...
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