Scheme 1. Diastereoselection and Enantiomeric Configuration At-Metal of Nonplanar Bis(N,O-chelate) Schiff Base Complexes Viewed along the C₂ Axis (Perpendicular to the Paper Plane): Λ as the Left-Handed Helicity, Δ as the Right-Handed Helicity along the C₂ Axis, for Complexes of Cobalt(II),¹⁹ Nickel(II),^21,23 Copper(II),^20,22,25 and Zinc(II)^24,26.

For some copper complexes, the sign of induction is reversed (see the text).²²