The asymmetric 1,3-dipolar cycloaddition of azomethineimines to homoallylic alcohols was achieved by utilizing diisopropyl (R,R)-tartrate as a chiral auxiliary to give the corresponding optically active trans-pyrazolidines with excellent regio-, diastereo-, and enantioselectivities. The catalytic use of diisopropyl (R,R)-tartrate was also effective in the presence of MgBr 2 .
The catalytic regio- and enantioselective 1,3-dipolar cycloaddition of azomethine imines to allyl alcohol was achieved by utilizing diisopropyl (R,R)-tartrate as a chiral auxiliary to afford the corresponding optically active trans-pyrazolidines with enantioselectivities up to 93% ee. Addition of MgBr2 was crucial to realize reproducible high enantioselectivity.
Asymmetric 1,3-Dipolar Cycloaddition Reaction of Azomethine Imines to Allyl Alcohol
The asymmetric1,3-dipolarcycloaddition of azomethine imines to allyl alcohol was achieved by utilizing diisopropyl (R,R)-tartrate as a chiral auxiliary to afford the corresponding optically activ...