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1.
Transfer of dithiolene ligands from [Ni(S2C2Ph2)2] to the dimolybdenum complex [Mo2(μ-C2R2)(CO)4Cp2] (R=CO2Me, Cp=η-C5H5) affords the first example of a dithiolene alkyne complex, [Mo2(μ-C2R2)(μ-S2C2Ph2)2Cp2], together with [Mo2(μ-SCRCR)(μ-SCPhCPh)Cp2] in which sulfur transfer from dithiolene to alkyne has occurred.  相似文献   
2.
The novel ruthenium dithiolene complexes [(arene)Ru{S2C2(COOMe)2}] (arene = C6H6 (1a), C6H4(Me)(iPr) (1b), C6Me6 (1c)) were synthesized. The equilibrium between complex 1a and the corresponding dimer [(C6H6)Ru{S2C2(COOMe)2}]2 (1a′) was confirmed in solution. The reaction of complex 1a with dimethyl- or diethylacetylene dicaboxylate gave the alkene-bridged adducts [(C6H6)Ru{S2C2(COOMe)2}{C2(COOR)2}] (R = Me (2a), Et (3a)) as [2 + 2] cycloaddition products formally. The reactions of complex 1a with diazo compounds also gave the alkylidene-bridged adducts [(C6H6)Ru{S2C2(COOMe)2}(CHR)] (R = H (4a), SiMe3 (5a), COOEt (6a)) as [2 + 1] cycloaddition products. The electrochemical behavior of complex 1a was investigated. The reductant of complex 1a was a stable species for several minutes. The oxidant of complex 1a was very unstable; the cation 1a+ formed was immediately converted to the corresponding cationic dimer 1a+. The cationic dimer 1a+ was stable for several minutes, and it was rapidly and quantitatively converted to the neutral complex 1a when it was reduced.  相似文献   
3.
The reaction of CuCl2-2H2O or NiCl2.6H2O with K2(C5H6S4) [potassium salt of 6,7-dihydro-5H-1,4-dithiepin-2,3-dithiolate] under nitrogen atmosphere resulted in the isolation of [Cu(C5H6S4)2]- or [Ni(C5H6S4)2]- as the tetrabutylammonium salt. Both complexes show characteristic IR and UV-Vis absorptions of transition metal dithiolenes. Cyclic voltammograms contain two waves indicating a two step electrochemical procedure [M(C5H6S4)2]0 = [M(C5H6S4)2]1-= [M(C5H6S4)2]2-. Single crystal structure study has been carried out on the nickel complex. Crystal of [Bu4N][Ni(C5H6S4)2] belongs to monoclinic space group P21/c with a=17.576(5), 6=10.883(2), c=17.773(4) A,B=91.07(2)0, Z=4, and o(calcd.)=1.348 g/cm3. Final result is R=0.059 for 2959 reflections. The NiS4 core exhibits square planar coordination with average Ni-S bond length of 2.134(5) A. There are not anion pairs in crystal. The anions stack along a and c axes while the cations intercalate in them. The nearest S-S contact is 4.429 A. The solid powder ESR s  相似文献   
4.
Eight new sulfur-rich [CpCo(dithiolene)] complexes were synthesized from [Zn(dmit)2]2− as a starting material. The structures, electrochemical behavior and electronic absorption spectra of the sulfur-rich [CpCo(S2C2S2Y)] complexes could be compared with the early data of analogous Ni complexes. [CpCo(pddt)] (Y = -(CH2)3-), [CpCo(dpdt)] (Y = -CH2C(CH2)CH2-), [CpCo(bddt)] (Y = -(CH2)4-), [CpCo(dtdt)] (Y = -CH2SCH2-) and [CpCo(poddt)] (Y = -CH2C(O)CH2-) crystallized in all isostructural with the corresponding paramagnetic [CpNi(dithiolene)] complexes, but [CpCo(dmid)] (Y = CO), [CpCo(dddt)] (Y = -(CH2)2-) and [CpCo(F2pddt)] (Y = -CH2CF2CH2-) crystallized in non-isostructural with them. These molecules are associated with intermolecular short S?S contacts in the crystals. [CpCo(F2pddt)] did not show any remarkable S?S contacts but indicated interesting fluorine segregation and Cp?Cp face-to-face interactions. Redox potentials of [CpCo(dithiolene)] complexes were obtained with the cyclic voltammetry measurements and dimerized by electrochemical oxidations. Electronic absorption spectra of [CpCo(dithiolene)] complexes showed visible absorption in the range of 585-701 nm as lowest energy wavelengths (? = 9800-11,800 M−1 cm−1) in solutions, and they were higher energy than those of [CpNi(dithiolene)] complexes (near-IR).  相似文献   
5.
This review paper summarizes the reactivities of metal dithiolene complexes based on the ‘coexistence of aromaticity and unsaturation’ in the five-membered metallacycle, the so-called metalladithiolene ring (MS2C2). The 16-electron [LM(dithiolene)] (LM = CpMIII, Cp*MIII, (C6R6)MII) complexes are coordinatively unsaturated and usually show M-S centered cycloaddition reactions with nucleophiles (e.g. diazoalkanes, organic azides, quadricyclane) and electrophiles (e.g. tetracyanoethylene oxide, activated acetylene). The resulting metalladithiolene cycloadducts, which have three-membered M-S-C or M-S-N rings, further react with protic acids or PR3 to undergo the ring-opening reactions involving the M-C bond, M-S bond or M-N bond cleavages. Furthermore, diverse adduct dissociations are observed by thermal, photochemical or electrochemical redox reactions. Such reactions normally produce the original [LM(dithiolene)] complexes (non-adduct) and the eliminated fragments. Among them, the Co-S centered imido adduct [CpCo(dithiolene)(NR)] (R = Ts, Ms) reacted under thermal conditions in the presence of PR3 to undergo the intramolecular imido migration reaction to the Cp ligand, giving [(C5H4-NHR)Co(dithiolene)] complexes. The M-S centered multinuclear cluster complexes are obtained by the reaction of [LM(dithiolene)] with low valent M(CO)n complexes. The square-planar bis(dithiolene) complexes [M(dithiolene)2]0 (M = Ni, Pd, Pt) or tris(dithiolene) complexes [M(dithiolene)3]0 yield cycloaddition products with olefins. These reactions are due to ligand centered reactions made possible by a molecular orbital overlap between dithiolene LUMO and olefin HOMO. Similar ligand centered adducts are obtained by the reaction of dianionic [M(dithiolene)2]2− with haloalkanes or dihaloalkanes. Also these adducts of bis(dithiolene) complex are dissociated photochemically and electrochemically. This paper also describes the reactivities of organometallic o-carborane dithiolate complexes, which are generally formulated as [LM(S2C2B10H10)] (LM = CpCo, Cp*Rh, Cp*Ir, (p-cymene)Ru and (p-cymene)Os). Diverse addition reactions are reported; in particular, the reaction with acetylene involves B-H bond activation in the carborane moiety.  相似文献   
6.
报道了新近合成的二氰基二硫纶和菲咯啉-5,6-二酮混配锰(Ⅱ)、铁(Ⅱ)及钴(Ⅱ)配合物MLL′(L=mnt2-,1,2-二氰基乙烯-1,2-二硫醇离子;L′=phen-5,6-dione,菲咯啉-5,6-二酮)红外-远红外光谱实验数据。在红外及远红外光谱中,特征ν(CN),ν(CO),ν(CC),ν(CN),ν(C—S),ν(M—S),ν(M—N)吸收较强,远红外光谱表明配合物中M—S键比M—N键强。利用群论方法分析了标题配合物MLL′的简正坐标和配位模式,探讨了这类配合物的红外光谱与结构的关系。标题配合物中过渡金属离子与二氰基二硫纶和菲咯啉二酮形成四配位的畸变四面体构型,其对称性近似于C2和C2V。  相似文献   
7.
[CpCo(oxddt)] complex (2, oxddt = o-xylenediyldithioethylene-1,2-dithiolate, Cp = η5-cyclopentadienyl) was obtained from o-xylenediyldithioethylene-1,3-dithiol-2-one (OC(oxddt)) (1). 2 further reacted with diazoalkanes (N2CHR) to form some alkylidene-bridged adducts [CpCo(CHR)(oxddt)] (R = H (3a), SiMe3 (3b)). Adduct 3a further reacted with protic acids (HX) to give some S-methylated adducts [CpCo(X)(oxddt)(S-Me)] (X = Cl (4a), OCOCF3 (4c)), followed by the Co-C bond cleavage in the three-membered cobaltathiirane ring. Two different Z-shaped and U-shaped molecular structures were observed by X-ray diffraction studies. In the former structure (Z), the dithiolene and o-xylylene planes are located at almost parallel position each other, and in the latter structure (U), both planes are not parallel but the o-xylylene moiety is located closer to the dithiolene plane than the Z-shaped one. The Z-shaped structure involves 1 and 2. The U-shaped structure involves 3a, 3b, 4a and 4c. Complex 1 showed a one-dimensional chain through intermolecular π-π interaction in the crystal. Complex 2 had a dimeric interaction between dithioethylenedithiolate moieties (S2C2S2) in the oxddt. The SiMe3 group in 3b was placed at an exo-position with respect to the cobaltadithiolene ring due to a steric hindrance from the U-shaped oxddt ligand. In 4a, the X and Me groups are located at the opposite side of the dithiolene plane (anti-form) but in 4c, both groups are presented at the same side of the dithiolene plane (syn-form). The NMR analysis of 4a in solution indicated existence of both anti- and syn-isomers (7:1).  相似文献   
8.
The one-pot reaction of [CpMo(NO)(CO)2] with elemental sulfur and dimethyl acetylenedicarboxylate (C2Z2 (Z = COOMe)) gave the [2+2] cycloadduct of the mononuclear molybdenum dithiolene complex [CpMo(NO)(S2C2Z2)(C2Z2)] (1), and some binuclear complexes:[CpMo(NO)(S2C2Z2)]2 (2), [Cp2Mo2(NO)2S2(S2C2Z2)] (3) and [CpMo(NO)S2]2 (4).The reaction of [CpMo(NO)(Cl)(μ-Cl)]2 with OC{S2C2(COOMe)2} in the presence of sodium methoxide also produced complex 2 and the paramagnetic CpMo bisdithiolene complex [CpMo(S2C2Z2)2] (5, Z = COOMe).The structures of complexes 1-5 were determined by X-ray crystal structure analysis.The nitrosyl ligands of complexes 1-4 showed a linear coordination to the molybdenum center (the Mo-N-O bond angles = 169-174°), and their N-O bond lengths were 1.17-1.20 Å.In the binuclear complexes 2-4, two nitrosyl ligands were placed at cis-position.Complexes 1 and 2 were characterized by cyclic voltammetry and spectroelectrochemistry (visible and IR). The electrochemical reduction of the dimeric complex 2 formed the monomeric dithiolene complex[CpMo(NO)(S2C2Z2)] (X) whose lifetime was several minutes. When the anion X was electrochemically oxidized, the coordinatively unsaturated species X was generated, but it was immediately dimerized to afford the original dimeric complex 2. The reduction of the complex 1 included the elimination of the bridged DMAD moiety (C2Z2) to give the anion X.  相似文献   
9.
The cobalt dithiolene complex with the sulfonylamide-substituted Cp ligand [(C5H4-NHTs)Co{S2C2(COOMe)2}] (1, Ts = p-SO2C6H4Me) reacted with TsOH · H2O to give [(C5H4-NH2)Co{S2C2(COOMe)(H)}] (2), [(C5H4-NHTs)Co(S2C2H2)] (3) and [(C5H4-NHTs)Co{S2C2(COOMe)(H)}] (4). Complex 1 was dissolved in a basic aqueous solution, and the anion reacted with Me2SO4 to form the N-methylated product [{C5H4-N(Me)Ts}Co{S2C2(COOMe)2}] (5); the carboxylic acid complex [{C5H4-N(Me)Ts}Co{S2C2(COOMe)(COOH)}] (6) formed by a base hydrolysis. The X-ray crystal structures of complexes 4-6 and the methylsulfonylamide-substituted Cp complex [(C5H4-NHMs)Co{S2C2(COOMe)2}] (7, Ms = SO2Me) were determined. In the crystal structures of complexes 4 and 7, intermolecular hydrogen bondings of NH?O (ca. 2.1 Å) and NH?S (ca. 3.1 Å) were observed. Complex 6 showed the OH?O intermolecular hydrogen bonding (ca. 1.6 Å) of COOH moiety between two molecules, and these two molecules were assembling each other. Complexes 5 and 6 showed an intramolecular π-π interaction between the aromatic cobaltadithiolene and benzene rings, and complex 5 also has intermolecular π-π interactions between two benzene rings, and between two cobaltadithiolene rings.  相似文献   
10.
Tetracyanoethylene oxide (TCNEO) reacted with [CpCo(dithiolene)] (Cp = η5-cyclopentadienyl) complexes having 4-pyridyl or 3-pyridyl group to undergo a dicyanomethylation to the nitrogen atom on the pyridyl group. The reaction of [CpCo(S2C2(4Py)2)] (1) with TCNEO formed both the monodicyanomethylated [CpCo(S2C2(4Py)(4Py-C(CN)2))] (1a) and bisdicyanomethylated [CpCo(S2C2(4Py-C(CN)2)2)] (1b). [CpCo(S2C2(2Py)(4Py))] (2) reacted with TCNEO to give [CpCo(S2C2(2Py)(4Py-C(CN)2))] (2a) but no dicyanomethylation occurred on the 2-pyridyl group. 2 reacted with excess TCNEO to form the only dicyanomethylated acetylene derivative 2Py-CC-(4Py-C(CN)2) (2c), followed by a dissociation of the CpCoS2 fragment. The monodicyanomethylated [CpCo(S2C2(nPy-C(CN)2)(2-thienyl))] (n = 4 (4a) or 3 (5a)) complexes were also prepared from [CpCo(S2C2(nPy)(2-thienyl))] (n = 4 (4) or 3 (5)) and TCNEO. 1b was structurally characterized by X-ray diffraction study. The all dicyanomethylated [CpCo(dithiolene)] complexes showed the dithiolene LMCT absorption in the range of 605-644 nm (ε = 7000-9200 M−1 cm−1) and very strong absorption due to their pyridinium-dicyanomethylide moieties in near-UV region (e.g. 1b: λmax = 470 nm, ε = 43,400 M−1 cm−1). The CV of the all dicyanomethylated complexes exhibited two reduction waves. The first reduction is due to CoIII/CoII and the second one is due to the reduction of the pyridinium-dicyanomethylide moiety. The reduced 1b is stable enough for several minutes according to the visible spectroelectrochemical measurement. The ESR spectrum of 1b indicated eight hyperfine splittings due only to the interaction with the nuclear spin of cobalt (I = 7/2).  相似文献   
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