New binding modes for CSe: coinage metal coordination to a tungsten selenocarbonyl complex

Abstract

The new tungsten selenocarbonylate [NEt₄][W(CSe)(CO)₂(Tp*)] (Tp* = hydrotris(dimethylpyrazolyl)borate) reacts with group 11 reagents to provide σ–π or isoselenocarbonyl complexes of the form [WM(μ-CSe)(CO)₂(PR₃)_n(Tp*)] (M = Cu, Ag, Au; R = Ph, Cy; n = 1,3) depending on the phosphine stoichiometry or steric bulk. With [Cu(NCMe)₄]PF₆ and 1,4,7-trithiacyclononane ([9]aneS₃) however, the tetrametallic species [WCu₃(μ-CSe)(CO)₂([9]aneS₃)₃(Tp*)](PF₆)₂ is obtained in which one Cu coordinates to the WC triple bond and two coordinate to the Se atom.