Confining Phosphanes Derived from Cyclodextrins for Efficient Regio-and Enantioselective Hydroformylation

Two confining phosphane ligands derived from
either a- or b-cyclodextrin produce singly PIII-ligated metal
complexes with unusual coordination spheres. High-pressure
NMR studies have revealed that rhodium hydride complexes of
the same type are also formed under hydroformylation
conditions. This unique feature strongly favors the formation
of the branched aldehyde at the expense of the linear one with
high enantioselectivity in the rhodium-catalyzed hydroformylation
of styrene