Synthesis of ortho-phenyl substituted MeO-BIPHEP ligand and its application in Rh-catalyzed asymmetric hydrogenation
نویسندگان
چکیده
A new BIPHEP-type ligand with phenyl groups at the 3,30-positions, o-Ph-MeO-BIPHEP 3 was prepared. This ligand afforded excellent enantioselectivities when used in the Rh-catalyzed asymmetric hydrogenation of a-dehydroamino acid derivatives. The strong influence of o-phenyl groups of the ligand on the enantioselectivities of the reaction has been demonstrated by a comparison with its parent ligand MeO-BIPHEP. 2004 Published by Elsevier Ltd. MeO MeO PPh2 PPh2 P P equatorial
منابع مشابه
An ortho-substituted BIPHEP ligand and its applications in Rh-catalyzed hydrogenation of cyclic enamides.
[reaction: see text] An ortho-substituted BIPHEP ligand, o-Ph-hexaMeO-BIPHEP (1), is designed and synthesized. Compared with chiral biaryl phosphines without ortho substituents such as BINAP and MeO-BIPHEP, o-Ph-hexaMeO-BIPHEP shows higher enantioselectivities in Rh-catalyzed hydrogenation of cyclic enamides.
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