PREPARATION AND CHARACTERIZATION OF COPPER(I) COMPLEXES WITH UNSATURATED SMALL MOLECULES. CRYSTAL STRUCTURE DETERMINATION OF A COPPER CARBONYL COMPLEX STABILIZED BY A TRIS-CHELATING OXYGEN LIGAND.

Article abstract of DOI:10.1021/om00096a020

It is shown that the oxygen tripod ligands L** minus form surprisingly stable copper carbonyl complexes. Our qualitative study of the disproportionation/comproportionation equilibrium indicates, however, that the formation of the copper carbonyl complexes L//RCuCO is only slightly favored thermodynamically. The kinetic stability which seems very important could be imposed by the geometry of the tripod ligands L** minus . From the crystal structure of L//O//M//eCuCO and from models of the LCuCO compounds one can see that the copper center is much better shielded by the six OCH(CH//3)//2 groups in L//O//-//i//-//P//r CuCO than by the six OCH//3 or OC//2H//5 substituents in L//O//M//eCuCO and L// O//E//tCuCO. So far we have no quantitative data on the kinetics and the mechanism of the olefin exchange, but the observed influence of the size of the R substituents on the rate of exchange is in accord with an associative mechanism.