Direct enantioselective vinylogous Mannich-type reactions of acyclic enals: New experimental insights into the E/Z-dilemma

Chirality. 2019 Jul;31(7):522-533. doi: 10.1002/chir.23077. Epub 2019 May 15.

Abstract

The direct heterofunctionalization of acyclic α,β-unsaturated aldehydes with N-acylquinolinium ions contemplating the formation of two stereocentres is studied using dienamine catalysis. This work gives some new experimental insights on the remote stereocontrol in dienamine catalysis using unbiased aliphatic systems and large electrophiles, pointing to a (Z)-preference of the reactive configuration of the second double bond.

Keywords: Mannich reactions; N,O-acetals; acyclic enals; dienamine catalysis; vinylogous reactivity.