SYNTHESES AND MOLECULAR-STRUCTURES OF MONONUCLEAR RUTHENIUM CARBONYL-COMPLEXES CONTAINING 2,1-NAPHTHOQUINONE-2-OXIMATO LIGANDS

The reaction between [Ru-3(CO)(12)] and 2,1-naphthoquinone-2-oxime or known as 2-nitroso-1-naphthol afforded two isomeric mononuclear ruthen ium carbonyl complexes trans-[Ru(eta(2)-OC10H6NO)(2)(CO)(2)] 1 and cis -[Ru(eta(2)-OC10H6NO)(2)(CO)(2)] 2, in which the two bidentate 2-napht hoquinone-1-oximato ligands chelated on the ruthenium centre in differ ent spacial orientation via the coordination of naphtholic oxygen and oxime nitrogen atoms. Both 1 and 2 adopt a cis-dicarbonyl configuratio n and the carbonyl groups can be replaced by the N-donor ligands in th e presence of trimethylamine-N-oxide via the reaction intermediates, t rans-[Ru(eta(2)-OC10H6NO)(2)(CO)(NMe3)] 4 and cis-[Ru(eta(2)-OC10H6NO) (2)(CO)(NMe3)] 3a respectively. Complexes 1, 3a and 4 have been fully characterised by spectroscopic methods and their molecular structures were established by X-ray crystallographic analyses. (C) 1997 Elsevier Science S.A.