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A series of enantiopure aziridine carbinols were synthesized from commercially available starting materials ( l -serine and piperonylaldehyde), and characterized by 1 H NMR, 13 C NMR, HRMS, and IR. Their enantioselective induction behaviors were evaluated as chiral ligands in the asymmetric addition of diethylzinc and phenylethynylzinc to aryl and α,β-unsaturated aldehydes. Chiral aziridine carbinol 1h was found to catalyze the asymmetric addition of diethylzinc to aldehydes at low catalyst loadings (as little as 1 mol %), and the conversion rates were close to quantitative (up to 97% yield) with good to excellent enantiomeric excesses (up to 98% ee). A possible catalytic reaction mechanism is proposed.

A family of enantiopure β-aminoalcohols based on aziridine backbones were synthesized, and examined as chiral ligands for the copper(II)-catalyzed asymmetric Henry reaction of aromatic aldehydes with nitromethane, giving β-nitroalcohols in excellent yields (up to 93%) and moderate to good enantioselectivities (up to 82%). Moreover, possible transition states of the reaction are proposed. Copyright © 2014 John Wiley & Sons, Ltd.

A series of enantiopure aziridine carbinols were synthesized from commercially available starting materials ( l -serine and piperonylaldehyde), and characterized by 1 H NMR, 13 C NMR, HRMS, and IR. Their enantioselective induction behaviors were evaluated as chiral ligands in the asymmetric addition of diethylzinc and phenylethynylzinc to aryl and α,β-unsaturated aldehydes. Chiral aziridine carbinol 1h was found to catalyze the asymmetric addition of diethylzinc to aldehydes at low catalyst loadings (as little as 1 mol %), and the conversion rates were close to quantitative (up to 97% yield) with good to excellent enantiomeric excesses (up to 98% ee). A possible catalytic reaction mechanism is proposed.

A novel type of aziridine based ligands is synthesized and the derivative LIG is successfully applied under optimized conditions for the enantioselective Henry reaction of aromatic aldehydes (I).