The (29)Si NMR studies of chiral pentacoordinate silyl triflimides having a stereogenic center at silicon have revealed that a chiral silicon center is highly configurationally unstable. Such configurational instability has an enormously beneficial effect on the diastereo- and enantioselectivity of the catalytic asymmetric Diels-Alder reaction.

NMR Studies reveal that chiral pentacoordinate silyl triflimides derived from BINOL derivatives (I) with a silicon stereogenic center are highly configurationally unstable.