Synthesis, crystal structure and catalytic properties in the diastereoselective nitroaldol (Henry) reaction of new zinc(II) and cadmium(II) compounds

Abstract

The new complex [Zn(im)4](NO3)2 (1) was synthesized and crystallographically characterized. In the solid state, 1 is built up by [Zn(C3H4N2)]2+ cations and NO3− anions interlinked by NH⋯O hydrogen bonds which give rise to the formation of a 3D network.Complex 1 and [CdNa2(µ-L2)]n·6.34H2O (2), (L = 2-(2-(4,4-dimethyl-2,6-dioxocyclohexylidene)hydrazinyl)terephthalate) were used as catalysts for the Henry reaction, and high yields were obtained under optimum conditions. Both 1 and 2 act as very efficient catalysts for the Henry reaction and convert nitroethane and aldehydes to β-nitroalcohols in yields of up to 89%. The threo/erythro diastereoselectivity depends on the choice of catalyst and also the selection of the reaction substrate, reaching values up to 89:11.