Chiral Calcium Phosphate Catalyzed Asymmetric Alkenylation Reaction of Arylglyoxals with 3‑Vinylindoles

A highly
efficient alkenylation reaction of arylglyoxals with 3-vinylindoles
catalyzed by chiral calcium phosphate is described. Structurally diverse
allylic alcohols bearing indole and carbonyl units are prepared in
excellent yields, good diastereoselectivities, and high to excellent
enantioselectivities. These products are good building blocks for
the synthesis of polysubstituted chiral tetrahydrocarbozol-2-ones.
The mechanism study indicates that the most likely role of the catalyst
is to activate the hydrate of arylglyoxal and control the stereoselectivity
via desymmetric coordination.