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Updated: Jul 1, 2025

Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Carbon-chalcogen wires: alkynyltellurolatocarbynes
1Research School of Chemistry, Australian National University, Canberra, Australian Capital Territory, ACT 2601, Australia. a.hill@anu.edu.au.
Abstract:
The reactions of [W(CBr)(CO)2(Tp*)] (Tp* = tris(dimethylpyrazolyl)borate) with LiTeCCR (R = SiMe3, SiiPr3, iPr, Bu, Bu, Ph, C6H4Me-4, methylimidazol-2-yl) afford the first alkynyltellurolatocarbynes [W(CTeCCR)(CO)2(Tp*)]. Both the WC and CC multiple bonds are prone to metal addition as exemplified by treatment with [MCl(SMe2)] (M = Cu, Au) to afford the hexametallic complex [W2Cu4(μ-CTeCCSiiPr3)2Cl4(CO)4(Tp*)2] and [WAu(μ-CTeCCSiMe3)Cl(CO)2-(Tp*)] which evolves to the unusual hypervalent [WAu(μ-CTeCl4)(SMe2)(CO)2(Tp*)].
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