Enantioselective Aza-Diels-Alder Reaction Catalyzed by a Chiral Brønsted Acid: Effect of the Additive on the Enantioselectivity

Abstract

Danishefsky’s diene and aldimine underwent aza Diels-Alder reaction under the influence of chiral phosphoric acid derived from (R)-BINOL as a chiral Brønsted acid to afford piperidinone derivatives in good to high enantioselectivity. Addition of CH₃CO₂H improved both reactivity and enantioselectivity.

Key words

asymmetric synthesis - chiral Brønsted acid - aza-Diels-Alder reaction - Danishefsky’s diene

References and Notes

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17

The nine-membered cyclic structure of the complex was observed as an energy minimum by quantum chemical calculations (PM3, Spartan ’02, Wavefunction, Inc.).