A Bridging Selenoacyl Complex via Alkynylselenolatoalkylidyne Rearrangement

Carbon-chalcogen wires: alkynyltellurolatocarbynes

The reactions of [W(CBr)(CO)2(Tp*)] (Tp* = tris(dimethylpyrazolyl)borate) with LiTeCCR (R = SiMe3, SiiPr3, iPr, nBu, tBu, Ph, C6H4Me-4, methylimidazol-2-yl) afford the first alkynyltellurolatocarbynes [W(CTeCCR)(CO)2(Tp*)]. Both the WC and CC multiple bonds are prone to metal addition as exemplified by treatment with [MCl(SMe2)] (M = Cu, Au) to afford the hexametallic complex [W2Cu4(μ-CTeCCSiiPr3)2Cl4(CO)4(Tp*)2] and [WAu(μ-CTeCCSiMe3)Cl(CO)2-(Tp*)] which evolves to the unusual hypervalent [WAu(μ-CTeCl4)(SMe2)(CO)2(Tp*)].

Thiocarbonylphosphorane and arsorane ligands

Independently unstable thiocarbonylphosphorane or arsorane ligands SCAR₃ (A = P, As) are observed in the salts [W(η²-C,S-SCAR₃)(CO)₂(Tp*)]PF₆ [AR₃ = PCy₃, PMe_nPh_3-n: n = 0, 1, 2, AsMePh₂; Tp* = tris(dimethylpyrazolyl)borate] which arise from the reactions of phosphonio- or arsoniocarbynes [W(≡CAR₃)(CO)₂(Tp*)]⁺ with sulfur.

Heterobimetallic μ2-Halocarbyne complexes

The halocarbyne complexes [M(≡CX)(CO)2(Tp*)] (M = Mo, W; X = Cl, Br; Tp* = hydrotris(dimethylpyrazolyl)borate) react with [AuCl(SMe2)], [Pt(-H2C=CH2)(PPh3)2] or [Pt(nbe)3] (nbe = norbornene) to furnish rare examples of μ2-halocarbyne...

Auriferous alkynylselenolatoalkylidynes

Gold plating carbynes – The incorporation of gold(i) centres, either terminal or bridging, into alkynylselenolatocarbynes provides models for how such metallated carbon-wires might bind to metal surfaces.

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

The reaction of the new tungsten selenocarbonylate [Et₄N][W(CSe)(CO)₂(Tp*)] (Tp* = hydrotris(dimethyl-pyrazolyl)borate) with coinage metal based electrophiles provides access to a range of new bridging modes for the selenocarbonyl ligand.

Alkynylselenolatoalkylidynes (LnMC–Se–CCR) as building blocks for mixed metal/main-group extended frameworks

The reactions of [W(CBr)(CO)₂(Tp*)] (Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate) with lithium alkynylselenolates LiSeCCR (R = SiMe₃, SiⁱPr₃, ⁿBu, ^tBu, Ph, p-tolyl) afford the alkynylselenolatoalkylidyne complexes [W(CSeCCR)(CO)₂(Tp*)].

Isoselenocarbonyl complexes

The salt elimination reactions of [NEt₄][Mo(CSe)(CO)₂(Tp*)] ([NEt₄][2], Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate) with a range of metal halide complexes (ClML_n) have been investigated as a possible route to isoselenocarbonyl complexes [Mo(CSeML_n)(CO)₂(Tp*)].

Synthesis and reactivity of selenium functionalised allylidynes and propargylidynes

The reactions of the trimethylsilylpropargylidyne [W([triple bond, length as m-dash]CC[triple bond, length as m-dash]CSiMe3)(CO)2(Tp*)] (1: Tp* = hydrotris(dimethylpyrazolyl)borate) towards selenium centred reagents when treated with tetrabutylammonium fluoride (TBAF) were explored in order to prepare alkynylselenolato propargylidynes, e.g., [W([triple bond, length as m-dash]CC[triple bond, length as m-dash]CSePh)(CO)2(Tp*)]. Treating 1 with TBAF and PhSeSePh resulted in E and Z isomers of the vinylcarbyne (allylidyne) complex [W{[triple bond, length as m-dash]CC(SePh)[double bond, length as m-dash]CHSePh}(CO)2(Tp*)] in addition to traces of the trisubstituted derivative [W{[triple bond, length as m-dash]CC(SePh)[double bond, length as m-dash]C(SePh)2}(CO)2(Tp*)]. Reactions with PhSeCl resulted in the isolation of bimetallic bis-substituted allylidyne complex [(Tp*)(CO)2W[triple bond, length as m-dash]CC(SePh)[double bond, length as m-dash]C(SePh)C[triple bond, length as m-dash]CC[triple bond, length as m-dash]W(CO)2(CO)2(Tp*)] as well as the desired selenolatopropargylidyne [W([triple bond, length as m-dash]CC[triple bond, length as m-dash]CSePh)(CO)2(Tp*)].

Bis(alkylidynyl)tellurides and ditellurides

The tellurocarbonylates [M(CTe)(CO)₂(Tp*)]⁻ (M = Mo, W; obtained from [M(CBr)(CO)₂(Tp*)] and Li₂Te or [M(CLi)(CO)₂(Tp*)] and Te) react with an additional equivalent of [M(CBr)(CO)₂(Tp*)] to give bis(alkylidynyl)tellurides, [M₂(μ-CTeC)(CO)₄(Tp*)₂], whilst oxidation with [Fe(η-C₅H₅)₂]PF₆ affords the corresponding ditellurides [M₂(μ-CTe₂C)(CO)₄(Tp*)₂].

Rearrangement of bis(alkylidynyl)phosphines to phospha-acyls

A range of bis(alkylidynyl)phosphines RP{CM(CO)₂(Tp*)}₂ (M = Mo, W; R = Cl, Ph, Cy; Tp* = hydrotris(dimethylpyrazolyl)borate) are obtained from the reactions of [M(CLi)(CO)₂(Tp*)] with Cl₂PR or alternatively via the palladium(0)-mediated reactions of [W(CBr)(CO)₂(Tp*)] with RPH₂ (R = Py, Cy).