One-step templated synthesis of chiral organometallic salicyloxazoline complexes

The general approach to the synthesis of metal complexes begins with ligand synthesis, followed by ligand reaction with metal salts to afford organometallic complexes. Our research group first reported a one-pot multicomponent synthesis of chiral oxazolinyl-zinc complexes, in the presence of a large amount of ZnCl₂ (0.4-2.6 equiv.), with the yields of some products reaching 90%.

Our prior strategy was extended to use copper, cobalt, nickel, manganese, palladium or platinum salts as the third component. The one-step method used 1.0 equivalent of a metal salt, such as M(OAc)₂·nH₂O or MCl₂·nH₂O (M: Cu, Co, Ni, Pd or Pt, n = 1, 2 or 4), as a reagent to generate chiral salicyloxazoline complexes 1-8 in the reaction of 2-cyanophenol with different d- and l-amino alcohols.

Complexes 1-8 were obtained using a one-pot method with a sequential strategy. The reaction outcome was demonstrated for three-component reactions between metal salts, amino alcohols and 2-hydroxybenzonitrile to afford organometallic complexes in good yields (65-95%).