Co-ordination of alkali metals to sulfur-based organometallic ligands:133Cs and19F nuclear magnetic resonance studies of Cs[Mo(SC6F5)4(η5-C5H5)], the first example of caesium–fluorine spin–spin coupling

Abstract

Reactions of the complexes [Mol3(CO)2(η5-C5H5)] and [W(SC6F5)3(CO)(η5-C5H5)] with M′(SC6F5) give Cs[Mo(SC6F5)4(η5-C5H5)], M′[W(SC6F5)4(η5-C5H5)](M′= Cs, Rb or K) and solvated derivatives (M = Mo or W) M′[W(SC6F5)4(η5-C5H5)]·nthf (M′= Li, n= 4; or Na, n= 1); 133Cs and 19F NMR studies of Cs[M(SC6F5)4(η5-C5H5)] reveal co-ordination between the Cs+ and the organometallic anion and Cs–F coupling involving four o-fluorines of the SC6F5 groups, J(Cs–F)≈ 58 Hz.