Sulfonated Schiff base dimeric and polymeric copper(II) complexes: Temperature dependent synthesis, crystal structure and catalytic alcohol oxidation studies

The new sulfonated Schiff base copper compounds [Cu2L2(4,4′-bipy)(DMF)2] (1) and [Cu2L2(4,4′-bipy)]n·nH2O·nDMF (2), which act as good catalysts for the solvent- and additive-free microwave assisted peroxidative oxidation of primary or secondary alcohols, are isolated from the same reaction mixtures but at different temperatures. The coordination polymer 2, which can also be obtained from 1, comprehends a dimeric building block which is comparable to the basic structure of 1.