Alkynylselenolatoalkylidynes (LnMC–Se–CCR) as building blocks for mixed metal/main-group extended frameworks

Abstract

The reactions of [W(CBr)(CO)₂(Tp*)] (Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate) with lithium alkynylselenolates LiSeCCR (R = SiMe₃, SiⁱPr₃, ⁿBu, ^tBu, Ph, p-tolyl) afford the alkynylselenolatoalkylidyne complexes [W(CSeCCR)(CO)₂(Tp*)]. Desilylation of the SiMe₃ complex furnishes the parent [W(CSeCCH)(CO)₂(Tp*)], which may be further derivatised by deprotonation and treatment with triphenylcarbenium or triphenylmetal chlorides to give mixed-heteroatom products [W(CSeCCEPh₃)(CO)₂(Tp*)] (E = C, Si, Ge, Sn, Pb). This procedure extends to dichlorosilanes, whereby the unusual bimetallic complexes [(Tp*)(CO)₂WCSeCCSiRR′CCSeCW(CO)₂(Tp*)] (R, R′ = Ph, CH₃) are obtained, bridged by unsaturated units interrupted by two different main-group heteroatoms. Finally, the trimetallic analogues, [{(Tp*)(CO)₂W(CSeCC)}₃SiR] (R = Ph, Et), may be prepared in the same manner from appropriate organotrichlorosilanes.