Pentacoordinated bisaminoacyl hydrospirophosphoranes
were first
found to induce the asymmetric addition reactions as a novel chiral
organic framework. Asymmetric addition reactions of bisaminoacyl hydrospirophosphoranes
with aromatic aldehyde and in situ generated imine were investigated,
and the corresponding α-hydroxyspirophosphonates and α-amino
spirophosphonates were obtained. The addition reaction of hydrospirophosphoranes
with ΔP configuration showed better stereoselectivity
than that with ΛP configuration, not only for the
addition reaction to aromatic aldehyde but also to in situ generated
imine. Furthermore, the stereochemical mechanisms of asymmetric addition
reactions induced by pentacoordinated hydrospirophosphorane were proposed
by 31P NMR tracing experiment and X-ray diffraction analysis.