NOVEL TYPES OF HYDROGEN-BONDING WITH TRANSITION-METAL PI-COMPLEXES AND HYDRIDES

This review deals with the results of investigations of novel types of hydrogen bond involving transition metal complexes, namely H-bonds wi th a metal atom (XH...M) and those with the hydride hydrogen atom (XH. ..HM) as a base, as well as those with cationic hydrides as proton don ors with organic bases ([MH](+)...B). Spectral, thermodynamic and stru ctural characteristics of intra- and intermolecular hydrogen bonds are described. The influence of the nature of the metal atom, and of elec tronic and steric properties of ligands on the proton donor ability of the metal atom and hydride hydrogen are discussed. Studies of proton transfers occurring through intermediate hydrogen bonds are also analy sed. (C) 1997 Published by Elsevier Science S.A.