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The new bis(alkynyl)mercurial Hg{C≡CSeC≡W(CO)2(Tp*)}2 (Tp* = tris(dimethylpyrazolyl)borate) forms adducts with fluoride and phenathroline, the structures of which are interpreted in the context of two-coordinate mercury presenting a σ-torroid for spodium bonding. [ABSTRACT FROM AUTHOR]

The halocarbyne complexes [M(≡CX)(CO)2(Tp*)] (M = Mo, W; X = Cl, Br; Tp* = hydrotris(dimethylpyrazolyl)borate) react with [AuCl(SMe2)], [Pt(η2-H2C＝CH2)(PPh3)2] or [Pt(η2-nbe)3] (nbe = norbornene) to furnish rare examples of μ2-halocarbyne complexes [MAu(μ2-CX)Cl(CO)2(Tp*)], [MPt(μ2-CCl)(CO)2(PPh3)2(Tp*)] and [W2Pt(μ2-CCl)2(CO)4(Tp*)2]. The complex [WPt(μ2-CCl)(CO)2(PPh3)2(Tp*)] spontaneously rearranges to the μ2-carbido complex [WPt(μ2-C)Cl(CO)2(PPh3)2(Tp*)] during silica-gel chromatography. One phosphine ligand of [WPt(μ2-CCl)(CO)2(PPh3)2(Tp*)] is readily substituted by CO to afford [WPt(μ2-CCl)(CO)3(PPh3)(Tp*)]. These μ2-halocarbyne complexes have been interrogated by spectroscopic, crystallographic and computational methods, the latter by reference to data for terminal halocarbyne precursors [M(≡CX)(CO)2(Tp*)]. [ABSTRACT FROM AUTHOR]

The chemistry of transition metal carbynes, LnM≡CR, has historically been dominated by species bearing hydrocarbyl or amino 'R' substituents, with other elements appearing only sporadically. In recent years, carbynes and related 'C1' species bearing other main‐group substituents, particularly heavier elements of the p‐block, have begun to emerge. This review details the chemistry of heavier pnictogen‐functionalised C1 ligands, MCARn (A=P, As, Sb, Bi; n=0–3), including their syntheses, properties and reactivities, and how these are distinguished from more traditional carbyne complexes. Recent developments in the closely related phospha‐isonitrile LnM(CPR), cya‐phosphide and cya‐arside ligands, LnM(C≡A) (A=P, As), are also discussed. [ABSTRACT FROM AUTHOR]

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*)]. Desilylation of the SiMe3 complex furnishes the parent [W(≡CSeC≡CH)(CO)2(Tp*)], which may be further derivatised by deprotonation and treatment with triphenylcarbenium or triphenylmetal chlorides to give mixed-heteroatom products [W(≡CSeC≡CEPh3)(CO)2(Tp*)] (E = C, Si, Ge, Sn, Pb). This procedure extends to dichlorosilanes, whereby the unusual bimetallic complexes [(Tp*)(CO)2W≡CSeC≡CSiRR′C≡CSeC≡W(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(≡CSeC≡C)}3SiR] (R = Ph, Et), may be prepared in the same manner from appropriate organotrichlorosilanes. [ABSTRACT FROM AUTHOR]

The halocarbyne complexes [M(CX)(CO) 2 (Tp*)] (M = Mo, W; X = Cl, Br; Tp* = hydrotris(dimethylpyrazolyl)borate) react with [AuCl(SMe 2 )], [Pt(η 2 -H 2 CCH 2 )(PPh 3 ) 2 ] or [Pt(η 2 -nbe) 3 ] (nbe = norbornene) to furnish rare examples of μ 2 -halocarbyne complexes [MAu(μ 2 -CX)Cl(CO) 2 (Tp*)], [MPt(μ 2 -CCl)(CO) 2 (PPh 3 ) 2 (Tp*)] and [W 2 Pt(μ 2 -CCl) 2 (CO) 4 (Tp*) 2 ]. The complex [WPt(μ 2 -CCl)(CO) 2 (PPh 3 ) 2 (Tp*)] spontaneously rearranges to the μ 2 -carbido complex [WPt(μ 2 -C)Cl(CO) 2 (PPh 3 ) 2 (Tp*)] during silica-gel chromatography. One phosphine ligand of [WPt(μ 2 -CCl)(CO) 2 (PPh 3 ) 2 (Tp*)] is readily substituted by CO to afford [WPt(μ 2 -CCl)(CO) 3 (PPh 3 )(Tp*)]. These μ 2 -halocarbyne complexes have been interrogated by spectroscopic, crystallographic and computational methods, the latter by reference to data for terminal halocarbyne precursors [M(CX)(CO) 2 (Tp*)].

The chemistry of transition metal carbynes, L n M≡CR, has historically been dominated by species bearing hydrocarbyl or amino 'R' substituents, with other elements appearing only sporadically. In recent years, carbynes and related 'C 1 ' species bearing other main-group substituents, particularly heavier elements of the p-block, have begun to emerge. This review details the chemistry of heavier pnictogen-functionalised C 1 ligands, MCAR n (A=P, As, Sb, Bi; n=0-3), including their syntheses, properties and reactivities, and how these are distinguished from more traditional carbyne complexes. Recent developments in the closely related phospha-isonitrile L n M(CPR), cya-phosphide and cya-arside ligands, L n M(C≡A) (A=P, As), are also discussed., (© 2020 Wiley-VCH GmbH.)

The reactions of [W([triple bond, length as m-dash]CBr)(CO) 2 (Tp*)] (Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate) with lithium alkynylselenolates LiSeC[triple bond, length as m-dash]CR (R = SiMe 3 , Si i Pr 3 , n Bu, t Bu, Ph, p-tolyl) afford the alkynylselenolatoalkylidyne complexes [W([triple bond, length as m-dash]CSeC[triple bond, length as m-dash]CR)(CO) 2 (Tp*)]. Desilylation of the SiMe 3 complex furnishes the parent [W([triple bond, length as m-dash]CSeC[triple bond, length as m-dash]CH)(CO) 2 (Tp*)], which may be further derivatised by deprotonation and treatment with triphenylcarbenium or triphenylmetal chlorides to give mixed-heteroatom products [W([triple bond, length as m-dash]CSeC[triple bond, length as m-dash]CEPh 3 )(CO) 2 (Tp*)] (E = C, Si, Ge, Sn, Pb). This procedure extends to dichlorosilanes, whereby the unusual bimetallic complexes [(Tp*)(CO) 2 W[triple bond, length as m-dash]CSeC[triple bond, length as m-dash]CSiRR'C[triple bond, length as m-dash]CSeC[triple bond, length as m-dash]W(CO) 2 (Tp*)] (R, R' = Ph, CH 3 ) are obtained, bridged by unsaturated units interrupted by two different main-group heteroatoms. Finally, the trimetallic analogues, [{(Tp*)(CO) 2 W([triple bond, length as m-dash]CSeC[triple bond, length as m-dash]C)} 3 SiR] (R = Ph, Et), may be prepared in the same manner from appropriate organotrichlorosilanes.