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The novel heterobinuclear μ-vinylidene complex [Cp(CO) 2 Re(μ-C=CHPh)Pt(PPh 3 )(CO)] ( 1 ) was isolated from the reaction mixture of [Cp(CO) 2 Re(μ-C=CHPh)Fe(CO) 4 ] and Pt(PPh 3 ) 4 for the first time. Alternative high-yield synthetic approaches to 1 were developed including the reactions of [Cp(CO) 2 Re(μ-C=CHPh)Pt(PPh 3 ) 2 ] ( 2 ) with Co 2 (CO) 8 and Rh(acac)(CO) 2 . The complex was characterized by IR and 1 H, 13 C and 31 P NMR spectroscopy, a molecular structure of 1 was determined by X-ray diffraction analysis. The electrochemical behavior of the new complex was studied by cyclic voltammetry at platinum or glassed carbon electrodes and by dc polarography at a dropping mercury electrode. [ABSTRACT FROM AUTHOR]

The gold acetylide complex 20 endowed with a biaryl backbone provides opportunities for a study on the formation and fate of gold vinylidenes. Although the formyl group in 20 is not sufficiently electrophilic to get attacked by the acetylide in proximity, its activation with TBSOTf (TBSOTf= tert-butyldimethylsilyl trifluoromethanesulfonate) at low temperature triggered instantaneous formation of a gold vinylidene ( 21). This metastable species evolved into the cationic gold carbene complex 22 bearing a phenanthrene unit and a hydroxyl group at the aurated center; the recorded data suggest that this product might be better viewed as an acylgold species protonated by triflic acid. The use of [Me3O⋅BF4] as the activating agent led to formation of the analogous Fischer-type carbene 24, whereas replacement of gold by the [CpRu(PPh3)2]+ fragment allowed the ruthenium vinylidene 27 to be isolated, which closely resembles the proposed gold intermediate 21. The starting gold complex 20, the derived products 22 and 24, as well as vinylidene 27 were characterized by X-ray diffraction. [ABSTRACT FROM AUTHOR]

Structures and relative energies of binuclear iron-manganese complexes with the phosphine ligand L, which exist in vinylidene Cp(CO)(L)MnFe(μ-C=CHPh)(CO) ( 2) and benzylidene ketene η-{C[Mn(CO)(L)Cp]∙ ∙(CO)CHPh}Fe(CO) ( 3) forms are calculated by the B3LYP density functional method. Four isomers with different positions of ligand L relative to the phenyl ring (conformers a and b) and the substituent Ph relative to the С=С bond (conformers E and Z) are considered for each form and their relative stability is determined. It is shown that all isomers of 2 have approximately the same energy (within 4 kcal/mol) whereas the energies of isomers of 3 differ within 21 kcal/mol. Isomer 3Ea in which the PPh ligand contacts with the phenyl substituent of the vinylidene group is most energetically favorable. It is found that with an increase in the L ligand size in the order PH < PHPh < PHPh < PPh the Mn-P bond length increases to 2.37 Å in the most stable isomer of form 3 and to 2.43 Å in the isomers of 2 and three conformers of 3. A more substantial increase in the Mn-P bond length in complexes 2 and 3 correlates with their lower stability as compared to isomer Ea of 3, which is consistent with experimental data on the presence of only one conformer 3Ea in solution. [ABSTRACT FROM AUTHOR]

The novel tetranuclear di-vinylidene complex Cp 2 (CO) 4 RePd(μ 2 -C CHPh)RePd(μ 3 -C CHPh)(dppe) was isolated and characterized by X-ray diffraction. This cluster consists of two RePd fragments linked to each other through the bonding of the palladium atom in the [Cp(CO) 2 RePd(μ-C CHPh)] fragment to the carbonyl and vinylidene ligands in the Cp(CO) 2 RePd(μ-C CHPh)(dppe) fragment. [ABSTRACT FROM AUTHOR]

The single crystal X-ray diffraction study of the heterometallic cluster CpMnFePt(μ-C=CHPh)(PPh)(CO) is performed. The crystallographic characteristics are as follows: a = 32.356(15) Å, b = 11.754(5) Å, c = 20.114(9) Å, β = 115.707(6)°, V = 6893(5) Å, space group C2/ c, Z = 8, d = 1.741 g/cm. The cluster molecule contains a bridging phenylvinylidene ligand coordinated to a metallic core in the form of a Mn-Fe-Pt chain (the Mn-Fe and Fe-Pt bond lengths are 2.6768(14) Å and 2.6280(11) Å respectively and the Mn⋯Pt distance is 3.6425(19) Å). [ABSTRACT FROM AUTHOR]

The reaction of [Cp(CO) 2 Re C CHPh] ( 1 ) with [Pd(PPh 3 ) 4 ] followed by the treatment of resulting [Cp(CO) 2 RePd(μ-C CHPh)(PPh 3 ) 2 ] ( 2 ) with diphosphines (dppe, dppp) gave new complexes [Cp(CO) 2 RePd(μ-C CHPh)(dppe)] ( 3 ) and [Cp(CO) 2 RePd(μ-C CHPh)(dppp)] ( 4 ). Treatment of the synthesized complexes with [Fe 2 (CO) 9 ] led to mixtures of [Cp(CO) 2 ReFe(μ-C CHPh)(CO) 4 ] ( 5 ), [(dppe)PdFe 2 (CO) 8 ] ( 6 ), [CpReFe 2 (μ 3 -C CHPh)(CO) 8 ] ( 7 ), [CpReFePd(μ 3 -C CHPh)(CO) 5 (dppe)] ( 8 ) and of 5 , [(dppp)PdFe 2 (CO) 8 ] ( 9 ), [CpReFePd(μ 3 -C CHPh)(CO) 5 (dppp)] ( 10 ), respectively. The main products of both reactions were trinuclear μ 3 -vinylidene clusters 8 and 10 . Reactions of the trinuclear μ 3 -vinylidene ReFePd clusters 8 and 10 with Fe 2 (CO) 9 were also studied. New complexes were characterized by IR, 1 H, 13 C, 31 P NMR spectroscopy and cyclic voltammetry. The structure of [CpReFe 2 (μ 3 -C CHPh)(CO) 8 ] was determined by single-crystal X-ray diffraction. [ABSTRACT FROM AUTHOR]

Abstract: The interaction between Cp(CO)2Re C CHPh (1) and CuCl results in the new heterometallic μ-vinylidene complex [Cp(CO)2ReCu(μ2-C CHPh)(μ2-Cl)]2 (2) characterized earlier by IR and 1H, 13C NMR spectra. The molecular structure of compound 2 has been determined by X-ray diffraction analysis, revealing a dimer structure with two binuclear fragments linked to each other by asymmetric chloride bridges. The electrochemical behavior of 2 in acetonitrile was studied by cyclic voltammetry at a Pt-electrode. [Copyright &y& Elsevier]

Reaction of Cp(CO)2Re=C=CHPh (1) with Pt(PPh3)4 and subsequent treatment of Cp(CO)2RePt(μ–C=CHPh)(PPh3)2 (2) with diphosphines P–P = dppe, dppp afforded new complexes Cp(CO)2RePt(μ–CCHPh)(P–P) (4, 5). The structures of Cp(CO)2RePt(μ–C=CHPh)(dppp) (5) and Cp(CO)2MnPt(μ–C=CHPh)(dppp) (10) have been determined by single crystal XRD. The influence of the nature of M = Re, Mn and L2 = (PPh3)2, dppm, dppe, dppp at the Pt atom on the structural, IR and 1H, 13C and 31P NMR spectroscopic characteristics of complexes Cp(CO)2MPt(μ–C=CHPh)(L2) (2–5, 7–10) is considered. [ABSTRACT FROM AUTHOR]

The X-ray diffraction study of a new heterometallic cluster CpReFePt(μ3-C=CHPh)(CO)[P(OPr)] is performed. The crystallographic characteristics are as follows: a = 11.0275(4) Å, b = 33.0367(12) Å, c = 12.2691(5) Å, β = 98.3660(10)°, V = 4422.2(3) Å, space group P2/ n, Z = 4, d = 1.744 g/cm. The cluster contains the phenylvinylidene ligand coordinated with a trimetallic core in the form of a Re-Fe-Pt chain (the Re-Fe and Fe-Pt bond lengths are 2.794(7) Å and 2.628(1) Å respectively; the Re···Pt distance is 3.354(1) Å). [ABSTRACT FROM AUTHOR]