Coordination polymers based on [Cp*Fe(η5-P5)]: solid-state structure and MAS NMR studies

Slow diffusion reactions of the pentaphosphaferrocene [Cp*Fe(η(5)-P(5))] (Cp*=η(5)-C(5)Me(5) (1)) with CuX (X=Cl, Br, I) in different stoichiometric ratios and solvent mixtures result in the formation of one- and two-dimensional polymeric compounds 2-6 with molecular formula [{Cu(μ-X)}{Cp*Fe(μ(3),η(5):η(1):η(1)-P(5))}](n) (X=Cl (2a), I (2'c)), [{Cu(μ-I)}{Cp*Fe(μ(3),η(5):η(1):η(1)-P(5))}](n) (3), [{CuX}{Cp*Fe(μ(4),η(5):η(1):η(1):η(1)-P(5))}](n) (X=Cl (4a), Br (4b), I (4c), Br (4'b), I (4'c)), [{Cu(3)(μ-I)(2)(μ(3)-I)}{Cp*Fe(μ(5),η(5):η(1):η(1):η(1):η(1)-P(5))}](n) (5) and [{Cu(4)(μ-X)(4)(CH(3)CN)}{Cp*Fe(μ(7),η(5):η(2):η(1):η(1):η(1):η(1):η(1)-P(5))}](n) (X=Cl (6a), Br (6b)), respectively. The polymeric compounds have been characterised by single-crystal X-ray diffraction analyses and, for selected examples, by magic angle spinning (MAS) NMR spectroscopy. The solid-state structures demonstrate the versatile coordination modes of the cyclo-P(5) ligand of 1, extending from two to five coordinating phosphorus atoms in either σ or σ-and-π fashion. In compounds 2a, 2'c and 3, two phosphorus atoms of 1 coordinate to copper atoms in a 1,2 coordination mode (2a, 2'c) and an unprecedented 1,3 coordination mode (3) to form one-dimensional polymers. Compounds 4a-c, 4'b, 4'c and 5 represent two-dimensional coordination polymers. In compounds 4, three phosphorus atoms coordinate to copper atoms in a 1,2,4 coordination mode, whereas in 5 the cyclo-P(5) ligand binds in an unprecedented 1,2,3,4 coordination mode. The crystal structures of 6a,b display a tilted tube, in which all P atoms of the cyclo-P(5) ligand are coordinated to copper atoms in σ- and π-bonding modes.     

Symmetrization in a phosphinidene-bridged complex to give a diphosphanediyl derivative with metal-centered reactivity

The phosphinidene complex [Mo(2)Cp(μ-κ(1):κ(1),η(5)-PC(5)H(4))(CO)(2)(η(6)-HMes*)] reacts with CO to give the diphosphanediyl derivative [Mo(2){μ-κ(1),η(5):κ(1),η(5)-(C(5)H(4))PP(C(5)H(4))}(η(6)-HMes*)(2)]. The latter compound features unreactive lone electron pairs at phosphorus, which instead contribute to the electronic communication between metal centers via a weak π(PP)-bonding interaction. As a result, this complex displays metal-centered acid-base and redox behavior.     

Dimolybdenum cyclopentadienyl complexes with bridging chalcogenophosphinidene ligands

The reactions of the phosphinidene-bridged complex [Mo(2)Cp(2)(μ-PH)(η(6)-HMes*)(CO)(2)] (1), the arylphosphinidene complexes [Mo(2)Cp(2)(μ-κ(1):κ(1),η(6)-PMes*)(CO)(2)] (2), [Mo(2)Cp(2)(μ-κ(1):κ(1),η(4)-PMes*)(CO)(3)] (3), [Mo(2)Cp(2)(μ-κ(1):κ(1),η(4)-PMes*)(CO)(2)(CN(t)Bu)] (4), and the cyclopentadienylidene-phosphinidene complex [Mo(2)Cp(μ-κ(1):κ(1),η(5)-PC(5)H(4))(η(6)-HMes*)(CO)(2)] (5) toward different sources of chalcogen atoms were investigated (Mes* = 2,4,6-C(6)H(2)(t)Bu(3); Cp = η(5)-C(5)H(5)). The bare elements were appropriate sources in all cases except for oxygen, in which case dimethyldioxirane gave the best results. Complex 1 reacted with the mentioned chalcogen sources at low temperature, to give the corresponding chalcogenophosphinidene derivatives [Mo(2)Cp(2){μ-κ(2)(P,Z):κ(1)(P)-ZPH}(η(6)-HMes*)(CO)(2)] (Z = O, S, Se, Te; P-Se = 2.199(2) ?). The arylphosphinidene complex 2 was the least reactive substrate and gave only chalcogenophosphinidene derivatives [Mo(2)Cp(2)(μ-κ(2)(P,Z):κ(1)(P),η(6)-ZPMes*)(CO)(2)] for Z = O and S (P-O = 1.565(2) ?), along with small amounts of the dithiophosphorane complex [Mo(2)Cp(2)(μ-κ(2)(P,S):κ(1)(S'),η(6)-S(2)PMes*)(CO)(2)], in the reaction with sulfur. The η(4)-complexes 3 and 4 reacted with sulfur and gray selenium to give the corresponding derivatives [Mo(2)Cp(2)(μ-κ(2)(P,Z):κ(1)(P),η(4)-ZPMes*)(CO)(2)L] (L = CO, CN(t)Bu), obtained respectively as syn (Z = Se; P-Se = 2.190(1) ? for L = CO) or a mixture of syn and anti isomers (Z = S; P-S = 2.034(1)-2.043(1) ?), with these diastereoisomers differing in the relative positioning of the chalcogen atom and the terminal ligand at the metallocene fragment, relative to the Mo(2)P plane. The cyclopentadienylidene compound 5 reacted with all chalcogens, and gave with good yields the chalcogenophosphinidene derivatives [Mo(2)Cp(μ-κ(2)(P,Z):κ(1)(P),η(5)-ZPC(5)H(4))(η(6)-HMes*)(CO)(2)] (Z = S, Se, Te), these displaying in solution equilibrium mixtures of the corresponding cis and trans isomers differing in the relative positioning of the cyclopentadienylic rings with respect to the MoPZ plane in each case. The sulfur derivative reacted with excess sulfur to give the dithiophosphorane complex [Mo(2)Cp(μ-κ(2)(P,S):κ(1)(S'),η(5)-S(2)PC(5)H(4))(η(6)-HMes*)(CO)(2)] (P-S = 2.023(4) and 2.027(4) ?). The structural and spectroscopic data for all chalcogenophosphinidene complexes suggested the presence of a significant π(P-Z) bonding interaction within the corresponding MoPZ rings, also supported by Density Functional Theory calculations on the thiophosphinidene complex syn-[Mo(2)Cp(2)(μ-κ(2)(P,S):κ(1)(P),η(4)-SPMes*)(CO)(3)].     

Indenyl ring slippage in crown thioether complexes [IndMo(CO)2L]+ and C-S activation of trithiacyclononane: experimental and theoretical studies

The macrocycle 1,4,7-trithiacyclononane (ttcn) reacts with [(η(5)-Ind)Mo(CO)(2)(NCMe)(2)](+) (or [(η(5)-Ind)Mo(CO)(2)(κ(2)-dme)](+)) to give [(η(3)-Ind)Mo(CO)(2)(κ(3)-ttcn)](+) as the BF(4)(-) salt (1), but its reaction with [(η(5)-Ind)Mo(CO)(2)(C(3)H(6))(FBF(3))] affords the C-S bond cleavage product [(η(5)-Ind)Mo(CO)(κ(3)-1,4,7-trithiaheptanate)]BF(4) (6), which has been characterised by X-ray crystallography (Ind = C(9)H(7), indenyl). In contrast to ttcn, the macrocycles 1,3,5-trithiane (tt) and 1,4,7,10-tetrathiacyclododecane (ttcd) fail to induce changes in the coordination mode of indenyl: tt and ttcd react with [(η(5)-Ind)Mo(CO)(2)(NCMe)(2)](+) (or [(η(5)-Ind)Mo(CO)(2)(κ(2)-dme)](+)) to give [(η(5)-Ind)Mo(CO)(2)(κ(2)-tt)](+) (2), characterised by X-ray crystallography, and [(η(5)-Ind)Mo(CO)(2)(κ(2)-ttcd)](+) (3), respectively. The cyclopentadienyl (Cp = C(5)H(5)) analogues [(η(5)-CpMo(CO)(2)(κ(2)-tt)](+) (4) and [(η(5)-CpMo(CO)(2)(κ(2)-ttcn)](+) (5) have also been synthesised and 5 characterised by X-ray crystallography. DFT calculations showed that the η(5)-Ind/Cp coordination mode is always the most stable. However, a molecular dynamics study of the macrocycles conformations revealed that the major conformer of ttcn was a chair, which favoured κ(3) coordination. As indenyl complexes undergo slippage with a small barrier (<10 kcal mol(-1)), the kinetically preferred species [(η(3)-Ind)Mo(CO)(2)(κ(3)-ttcn)](+) (1) is the observed one. The conversion to 6 proceeds stepwise, with loss of ethylene followed by loss of CO, as calculated by DFT, with a barrier of 38.7 kcal mol(-1), consistent with the slow uncatalysed reaction.     

A nonacoordinated bridging selenide in a tricapped trigonal prismatic geometry identified in undecanuclear copper clusters: syntheses, structures, and DFT calculations

Undecanuclear copper clusters, [Cu(11)(micro(9)-Se)(micro(3)-Br)(3)[Se(2)P(OR)(2)](6)] (R = Et, Pr, (i)Pr) (1a-c), were isolated along with closed-shell ion-centered cubes, [Cu(8)(micro(8)-Br)[Se(2)P(OR)(2)](6)] (PF(6)) (2a-c) and [Cu(8)(micro(8)-Se)[Se(2)P(OR)(2)](6)] (3a-c), from the reaction of [Cu(CH(3)CN)(4)](PF(6)), NH(4)[Se(2)P(OR)(2)], and Bu(4)NBr in a molar ratio of 2:3:2 in CH(2)Br(2). The molecular formulations of these clusters were confirmed by elemental analysis, positive FAB mass spectrometry, and multinuclear NMR ((1)H, (31)P, and (77)Se). (77)Se NMR spectra of Cu(11) clusters (1a-c) are of special interest as two inequivalent selenium nuclei of the diselenophosphate (dsep) ligand exhibit different scalar coupling patterns with the adjacent phosphorus nuclei. X-ray analysis of 1c reveals a Cu(11)Se core stabilized by three bromide and six dsep ligands. The central core adopts the geometry of a 3,3,4,4,4-pentacapped trigonal prism with a selenium atom in the center. The coordination geometry for the nonacoordinate selenium atom is tricapped trigonal prismatic. The X-ray structure 2a or 2c consists of a cationic cluster in which eight copper ions are linked by six diselenophosphate ligands with a central micro(8)-Br ion. The shape of the molecule is a bromide-centered distorted Cu(8) cube. Each diselenophosphate ligand occupies square faces of the cube and adopts a tetrametallic tetraconnective coordination pattern. Each copper atom of the cube is coordinated by three selenium atoms with a strong interaction with the central bromide ion. Molecular orbital calculations at the B3LYP level of the density functional theory have been carried out to study the Cu-micro(9)-Se interactions for clusters [Cu(11)(micro(9)-Se)(micro(3)-X)(3)[Se(2)P(OR)(2)](6)] (X = Br, I). Calculations show that the formal bond order of each Cu-micro(9)-Se bond is slightly smaller than half of those calculated for the terminal Cu-micro(2)-Se bonds.     

2-Benzoylpyridine thiosemicarbazone as a novel reagent for the single pot synthesis of dinuclear Cu(I)-Cu(II) complexes: formation of stable copper(II)-iodide bonds

2-Benzoylpyridine thiosemicarbazone {R(1)R(2)C(2)=N(2)·N(3)H-C(1)(=S)-N(4)H(2), R(1) = py-N(1), R(2) = Ph; Hbpytsc} with copper(I) iodide in acetonitrile-dichloromethane mixture has formed stable Cu(II)-I bonds in a dark green Cu(II) iodo-bridged dimer, [Cu(2)(II)(μ-I)(2)(η(3)-N(1),N(2),S-bpytsc)(2)] 1. Copper(I) bromide also formed similar Cu(II)-Br bonds in a dark green Cu(II) bromo-bridged dimer, [Cu(2)(II)(μ-Br)(2)(η(3)-N(1),N(2),S-bpytsc)(2)] 3. The formation of dimers 1 and 3 appears to be due to a proton coupled electron transfer (PCET) process wherein copper(I) loses an electron to form copper(II), and this is accompanied by a loss of -N(3)H proton of Hbpytsc ligand resulting in the formation of anionic bpytsc(-). When copper(I) iodide was reacted with triphenylphosphine (PPh(3)) in acetonitrile followed by the addition of 2-benzoylpyridine thiosemicarbazone in dichloromethane (Cu?:?PPh(3)?:?Hbpytsc in the molar ratio 1:1:1), both Cu(II) dimer 1 and an orange Cu(I) sulfur-bridged dimer, [Cu(2)(I)I(2)(μ-S-Hbpytsc)(2)(PPh(3))(2)] 2 were formed. Copper(I) bromide with PPh(3) and Hbpytsc also formed Cu(II) dimer 3 and an orange Cu(I) sulfur-bridged dimer, [Cu(2)(I)Br(2)(μ-S-Hbpytsc)(2)(PPh(3))(2)] 4. While complexes 2 and 4 exist as sulfur-bridged Cu(I) dimers, 1 and 3 are halogen-bridged. The central Cu(2)S(2) cores of 2 and 4 as well as Cu(2)X(2) of 1 (X = I) and 3 (X = Br) are parallelograms. One set of Cu(II)-I and Cu(II)-Br bonds are short, while the second set is very long {1, Cu-I, 2.565(1), 3.313(1) ?; 3, Cu-Br, 2.391(1), 3.111(1) ?}. The Cu···Cu separations are long in all four complexes {1, 4.126(1); 2, 3.857(1); 3, 3.227(1); 4, 3.285(1) ?}, more than twice the van der Waals radius of a Cu atom, 2.80 ?. The pyridyl group appears to be necessary for stabilizing the Cu(II)-I bond, as this group can accept π-electrons from the metal.     

An unknown coordination mode of the phosphite unit and a carbon-free heterocycle in two different heterobimetallic alumophosphites

The unique alumophosphite reagent LAl(SH)(mu-O)P(OEt)2 was prepared and used for the synthesis of the heterobimetallic alumophosphites [{kappa2-S,P-LAl(S)(mu-O)P(OEt)2}2Zn] and [{kappa4-S,O,O-LAl(SLi)(mu-O)P(OEt)2}2]. The first contains a rare example of two carbon-free five-membered heterocycles (Al-S-Zn-P-O) connected in a spiro fashion through the zinc atom, whereas the second possesses an unknown example of a coordination environment of a phosphite unit M-O-P(mu-OEt)2M with an uncoordinated lone electron pair on the phosphorus center.     

Metal-dependent and redox-selective coordination behaviors of metalloligand [MoV(1,2-benzenedithiolato)3]- with CuI/AgI ions

The synthesis and characterization of two coordination polymers, {Cu(I)[Mo(V)(bdt)(3)]·0.5Et(2)O}(n) (1·0.5Et(2)O, bdt: o-benzenedithiolato) and {Ag(I)[Mo(V)(bdt)(3)]}(n) (2), composed of redox-active [Mo(V)(bdt)(3)](-) metalloligand with Cu(I) and Ag(I) ions are reported. The complexation reactions of [Mo(V)(bdt)(3)](-) with Cu(II)(ClO(4))(2) or Ag(I)ClO(4) commonly lead to the formation of one-dimensional (1-D) coordination polymers. The presence of Cu(I) in 1·0.5Et(2)O strongly indicates that the Cu(II) ion is reduced during the complexation reaction with [Mo(V)(bdt)(3)](-), which acts as an electron donor. The total dimensionalities of the assembled structures of 1·0.5Et(2)O and 2 are significantly different and related to the type of additional metal ions, Cu(I) and Ag(I). In contrast to the isolated 1-D chain structure of 1·0.5Et(2)O, complex 2 has a three-dimensional (3-D) assembled structure constructed from additional π-π stacking interactions between adjacent [Mo(V)(bdt)(3)](-) moieties. These structural differences influence the solubility of the complexes in organic solvents; complex 1·0.5Et(2)O is soluble as origomeric species in highly polar solvents, while 2 is insoluble in organic solvents and water. Coordination polymers 1·0.5Et(2)O and 2 were investigated by UV-vis spectroscopy in the solid state, and that in solution together with their electrochemical properties were also investigated for 1 because of its higher solubility in polar organic solvents. Complex 1·0.5Et(2)O dissolved in CH(3)CN demonstrates concentration-dependent UV-vis spectra supporting the presence of coordinative interactions between [Mo(V)(bdt)(3)](-) moieties and Cu(I) ions to create the origomeric species even in solutions, an observation that is supported also by electrochemical experiments.     

Self-assembled 2D supramolecular networks of copper(I) carborane complexes through C-H..H-B dihydrogen bonding interactions

Three dinuclear copper(i) complexes with the formula [Cu(2)(mu-X)(2)(1,2-(P(i)Pr(2))(2)-1,2-C(2)B(10)H(10))(2)] (X = Cl (), Br (), I ()) containing the closo carborane diphosphine ligand 1,2-(P(i)Pr(2))(2)-1,2-C(2)B(10)H(10) have been prepared and characterized by elemental analysis, FT-IR and X-ray structure determination. The X-ray structure analyses revealed that the three complexes were isostructural and crystallized in the monoclinic system and space group C2/m. The carborane cage ligand was coordinated bidentately to the Cu(i) center through its two phosphorus atoms, and the coordination geometry around each copper atom was distorted tetrahedral. Two halogen atoms bridged the metal centers forming a dimer structure [Cu(2)(mu-X)(2)(1,2-(P(i)Pr(2))(2)-1,2-C(2)B(10)H(10))(2)], which were linked into 2D supramolecular networks through novel C-HH-B dihydrogen bonding interactions.     

Trigonal planar copper(I) complex: synthesis, structure, and spectra of a redox pair of novel copper(II/I) complexes of tridentate bis(benzimidazol-2'-yl) ligand framework as models for electron-transfer copper proteins

The copper(II) and copper(I) complexes of the chelating ligands 2,6-bis(benzimidazol-2'-ylthiomethyl)pyridine (bbtmp) and N,N-bis(benzimidazol-2'-ylthioethyl)methylamine (bbtma) have been isolated and characterized by electronic and EPR spectra. The molecular structures of a redox pair of Cu(II/I) complexes, viz., [Cu(bbtmp)(NO(3))]NO(3), 1, and [Cu(bbtmp)]NO(3), 2, and of [Cu(bbtmp)Cl], 3, have been determined by single-crystal X-ray crystallography. The cation of the green complex [Cu(bbtmp)(NO(3))]NO(3) possesses an almost perfectly square planar coordination geometry in which the corners are occupied by the pyridine and two benzimidazole nitrogen atoms of the bbtmp ligand and an oxygen atom of the nitrate ion. The light-yellow complex [Cu(bbtmp)]NO(3) contains copper(I) with trigonal planar coordination geometry constituted by the pyridine and two benzimidazole nitrogen atoms of the bbtmp ligand. In the yellow chloride complex [Cu(bbtmp)Cl] the asymmetric unit consists of two complex molecules that are crystallographically independent. The coordination geometry of copper(I) in these molecules, in contrast to the nitrate, is tetrahedral, with pyridine and two benzimidazole nitrogen atoms of bbtmp ligand and the chloride ion occupying the apexes. The above coordination structures are unusual in that the thioether sulfurs are not engaged in coordination and the presence of two seven-membered chelate rings facilitates strong coordination of the benzimidazole nitrogens and discourage any distortion in Cu(II) coordination geometry. The solid-state coordination geometries are retained even in solution, as revealed by electronic, EPR, and (1)H NMR spectra. The electrochemical behavior of the present and other similar CuN(3) complexes has been examined, and the thermodynamic aspects of the electrode process are correlated to the stereochemical reorganizations accompanying the redox changes. The influence of coordinated pyridine and amine nitrogen atoms on the spectral and electrochemical properties has been discussed.     

Luminescent Tetranuclear Copper（I） Phenylacetylide Complex with Cyclohexyl Isocyanide

1INTRODUCTIONThechemistryofmetalalkynylcomplexeshasattractedmuchattentioninrecentyearsduetothespecificinterestinstructuraltopologyandopticalproperties[1～6].Ithasbeendemonstratedthatoneofthefeasiblestrategiestoattainoligomericmetalalky-nylcomplexesistodepolymerizepolymericspeciesofmetalalkynylsbyusingorganicligandssuchasphosphines[7～11]andisocyanides[12～14].Insomecases,simplemetal-containingcomponentsarealsoavail-abletodepolymerizethepolymericmetalalkynyl,formingalkynyl-bridgedheterometa…     

Heterobimetallic oxalato-bridged Cu(II)Re(IV) complexes. Synthesis, crystal structure and magnetic properties

Three copper(II)-rhenium(IV) bimetallic complexes of formula [ReCl(4)(mu-ox)Cu(phen)(2)] (1), [ReCl(4)(mu-ox)Cu(phen)(2)].CH(3)CN (2), and [ReCl(4)(mu-ox)Cu(terpy) (H(2)O)][ReCl(4)(mu-ox)Cu(terpy)(CH(3)CN)] (3) (ox = oxalate anion, phen = 1,10-phenanthroline, and terpy = 2,2':6,2"- terpyridine) have been synthesized and their crystal structures determined by single-crystal X-ray diffraction. Complex 1 crystallizes in the triclinic system, space group P(-1), with a = 9.776(2), b = 11.744(3), c = 14.183(3) A, alpha =102.09(2) degrees, beta = 109.42(2) degrees, gamma = 107.11(2) degrees, and Z = 2, whereas 2 and 3 crystallize in the monoclinic system, space groups P2(1)/n and P2(1)/c, respectively, with a = 12.837(3), b = 17.761(4), c = 12.914(3) A, beta = 91.32(2) degrees, and Z = 4 for 2, and a = 8.930(2), b = 18.543(4), c = 27.503(6) A, beta = 94.67(2) degrees, and Z = 4 for 3. The structures of 1 and 2 are made up of neutral [ReCl(4)(mu-ox)Cu(phen)(2)] bimetallic units. Re(IV) and Cu(II) metal ions exhibit distorted octahedral coordination geometries, being bridged by a bis(bidentate) oxalato ligand. The presence of acetonitrile molecules of crystallization in 2 causes a somewhat greater separation between the bimetallic complexes and a different packing of these units in the crystal structure with respect to 1. The copper-rhenium separation across oxalato is 5.628(2) in 1 and 5.649(3) A in 2. The structure of 3 is made up of two different and neutral bimetallic units, [ReCl(4)(mu-ox)Cu(terpy)(H(2)O)] and [ReCl(4)(mu-ox)Cu(terpy)(CH(3)CN)]. In the first one, the oxalate group behaves as a bis(bidentate) ligand occupying one equatorial and one axial position in the elongated octahedral environment of Cu(II). The water molecule is axially coordinated. In the second one, the oxalate group behaves as a bidentate/monodentate ligand occupying the axial position in the square pyramidal environment of Cu(II). The acetonitrile molecule occupies a basal coordination position around the copper atom. These units are arranged in such a way that a chlorine atom of the first unit (Cl(1)) points toward the copper atom (Cu(2))of the second one (3.077(2) A for Cl(1)(.)Cu(2)), forming a tetranuclear species. The copper-rhenium separation across bis(didentate) oxalato is 5.504(3) A, whereas that through bidentate/monodentate oxalato is 5.436(2) A. The magnetic behavior of 2 and 3 has been investigated over the temperature range 1.8-300 K. A very weak and nearly identical antiferromagnetic coupling between Re(IV) and Cu(II) through bis(bidentate) oxalato occurs in 2 (J = -0.90 cm(-1)) and 3 (J = -0.83 cm(-1)); it is ferromagnetic in 3 through both the bidentate-monodentate oxalato (J = +5.60 cm(-1)) and the chloro (J = +0.70 cm(-1)) bridges.     

The coordination chemistry of selenophosphite ligands. Synthesis and characterization of heterometallic tetranuclear clusters [M{CpFe(CO)(2)P(Se)(OR)(2)}(3)](PF(6)) (M = Cu, Ag; R = (n)Pr, (i)Pr) and [Cu(mu-X) {CpFe(CO)(2)P(Se)(O(i)Pr)(2)}](2) (X = Cl, Br)

A neutral selenium donor ligand, [CpFe(CO)(2)P(Se)(OR)(2)] is used for the construction of Cu(I) and Ag(I) complexes with a well-defined coordination environment. Four clusters [M{CpFe(CO)(2)P(Se)(OR)(2)}(3)](PF(6)), (where M = Cu, R = (n)Pr, ; R = (i)Pr, and M = Ag, R = (n)Pr, ; R = (i)Pr, ) are isolated from the reaction of [M(CH(3)CN)(4)(PF(6))] (where M = Cu or Ag) and [CpFe(CO)(2)P(Se)(OR)(2)] in a molar ratio of 1 : 3 in acetonitrile at 0 degrees C. The reaction of [CpFe(CO)(2)P(Se)(O(i)Pr)(2)] with cuprous halides in acetone produce two mixed-metal, Cu(I)(2)Fe(II)(2) clusters, [Cu(mu-X) {CpFe(CO)(2)P(Se)(O(i)Pr)(2)}](2) (X = Cl, ; Br, ). All six clusters have been fully characterized spectroscopically ((1)H, (13)C, (31)P, and (77)Se NMR, IR), and by elemental analyses. X-Ray crystal structures of and consist of discrete cationic clusters in which three iron-selenophosphito fragments are linked to the central copper or silver atom via selenium atoms. Both clusters and crystallize in the noncentrosymmetric, hexagonal space group P6[combining macron]2c. The coordination geometry around the copper or silver atom is perfect trigonal-planar with Cu-Se and Ag-Se distances, 2.3505(7) and 2.5581(7) A, respectively. X-Ray crystallography also reveals that each copper center in neutral heterometallic clusters and is trigonally coordinated to two halide ions and a selenium atom from the selenophosphito-iron moiety. The structures can also be delineated as a dimeric unit which is generated by an inversion center and has a Cu(2)X(2) parallelogram core. The dihedral angle between the Cu(2)X(2) plane and the plane composed of Cp ring is found to be 24.62 and 84.58 degrees for compound and , respectively. Hence the faces of two opposite Cp rings are oriented almost perpendicular to the Cu(2)X(2) plane in , but are close to be parallel in . This is the first report of the coordination chemistry of the anionic selenophosphito moiety [(RO)(2)PSe](-), the conjugated base of a secondary phosphine selenide, which acts as a bridging ligand with P-coordination on iron and Se-coordination to copper or silver.     

Synthesis and Crystal Structure of [Cp_2Ln(OC(SEt)NPh )]_2

1 INTRODUCTION The insertion of unsaturated molecules into the lanthanide-ligand bond has attracted considerable attention, because it is a fundamental step for many metal-promoted transformations, in which some va- luable new methods for the formation of carbon- carbon and carbon-heteroatom bonds can be deve- loped and some complexes with novel structures or peculiar characters can be obtained[1~4]. Notably, in contrast to the wide reaction chemistry of organo- lanthanide alkyl (aryl), am…     

The Potential of Molybdenum Complexes Bearing Unsubstituted Heterodiatomic Group 15 Elements as Linkers in Supramolecular Chemistry

The reactions of tetrahedral molybdenum complexes bearing unsubstituted heterodiatomic Group 15 elements, [Cp₂Mo₂(CO)₄(μ,η²:η²‐PE)] (Cp=C₅H₅; E=As ( 1 ), Sb ( 2 )), with Cu^I halides afforded seven unprecedented neutral supramolecular assemblies. Depending on the Mo₂PE units and the Cu^I halide, the oligomers [?{Cp₂Mo₂(CO)₄}{μ₄,η²:η²:η²:η¹‐PE}?₄?{CuX}{Cu(μ‐X)}?₂] (E=As (X=Cl ( 3 ), Br ( 4 )); E=Sb (X=Cl ( 6 ), Br ( 7 ))) or the 1D coordination polymers [{Cp₂Mo₂(CO)₄}{μ₄,η²:η²:η¹:η¹‐PAs}{Cu(μ‐I)}]_n ( 5 ) and [{Cp₂Mo₂(CO)₄}{μ₄,η²:η²:η²:η¹‐PSb}₂{Cu(μ‐X)}₃]_n (X=I ( 8 ), Br ( 9 )) are accessible. These solid‐state aggregates are the first and only examples featuring the organometallic heterodiatomic Mo₂PE complexes 1 and 2 as linking moieties. DFT calculations demonstrate that complexes 1 and 2 present a unique class of mixed‐donor ligands coordinating to Cu^I centers via the P lone pair and the P?E σ‐bond, revealing an unprecedented coordination mode.     

Coordination site-dependent cation binding and multi-responsible redox properties of Janus-head metalloligand, [Mo(V)(1,2-mercaptophenolato)3

The redox-active fac-[Mo(V)(mp)(3)](-) (mp: o-mercaptophenolato) bearing asymmetric O- and S-cation binding sites can bind with several kinds of metal ions such as Na(+), Mn(II), Fe(II), Co(II), Ni(II), and Cu(I). The fac-[Mo(V)(mp)(3)](-) metalloligand coordinates to Na(+) to form the contact ion pair {Na(+)(THF)(3)[fac-Mo(V)(mp)(3)]} (1), while a separated ion pair, n-Bu(4)N[fac-Mo(V)(mp)(3)] (2), is obtained by exchanging Na(+) with n-Bu(4)N(+). In the presence of asymmetric binding-sites, the metalloligand reacts with Mn(II)Cl(2)·4H(2)O, Fe(II)Cl(2)·4H(2)O, Co(II)Cl(2)·6H(2)O, and Ni(II)Cl(2)·6H(2)O to afford UV-vis-NIR spectra, indicating binding of these guest metal cations. Especially, for the cases of the Mn(II) and Co(II) products, trinuclear complexes, {M(H(2)O)(MeOH)[fac-Mo(V)(mp)(3)](2)}·1.5CH(2)Cl(2) (3·1.5CH(2)Cl(2) (M = Mn(II)), 4·1.5CH(2)Cl(2) (M = Co(II))), are successfully isolated and structurally characterized where the M are selectively bound to the hard O-binding sites of the fac-[Mo(V)(mp)(3)](-). On the other hand, a coordination polymer, {Cu(I)(CH(3)CN)[mer-Mo(V)(mp)(3)]}(n) (5), is obtained by the reaction of fac-[Mo(V)(mp)(3)](-) with [Cu(I)(CH(3)CN)(4)]ClO(4). In sharp contrast to the cases of 1, 3·1.5CH(2)Cl(2), and 4·1.5CH(2)Cl(2), the Cu(I) in 5 are selectively bound to the soft S-binding sites, where each Cu(I) is shared by two [Mo(V)(mp)(3)](-) with bidentate or monodentate coordination modes. The second notable feature of 5 is found in the geometric change of the [Mo(V)(mp)(3)](-), where the original fac-form of 1 is isomerized to the mer-[Mo(V)(mp)(3)](-) in 5, which was structurally and spectroscopically characterized for the first time. Such isomerization demonstrates the structural flexibility of the [Mo(V)(mp)(3)](-). Spectroscopic studies strongly indicate that the association/dissociation between the guest metal ions and metalloligand can be modulated by solvent polarity. Furthermore, it was also found that such association/dissociation features are significantly influenced by coexisting anions such as ClO(4)(-) or B(C(6)F(5))(4)(-). This suggests that coordination bonds between the guest metal ions and metalloligand are not too static, but are sufficiently moderate to be responsive to external environments. Moreover, electrochemical data of 1 and 3·1.5CH(2)Cl(2) demonstrated that guest metal ion binding led to enhance electron-accepting properties of the metalloligand. Our results illustrate the use of a redox-active chalcogenolato complex with a simple mononuclear structure as a multifunctional metalloligand that is responsive to chemical and electrochemical stimuli.     

Assembly of bicyclic or monocyclic clusters from [(η5-C5Me5)2Mo2(μ3-S)4(CuMeCN)2]2+ with tetraphosphine or N,P mixed ligands: syntheses, structures and enhanced third-order NLO performances

Reactions of the preformed cluster [(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)(MeCN)(2)](ClO(4))(2) (1) with two tetraphosphine ligands, 1,4-N,N,N',N'-tetra(diphenylphosphanylmethyl)benzene diamine (dpppda) and N,N,N',N'-tetra(diphenylphosphanylmethyl)ethylene diamine (dppeda), produced two bicyclic clusters {[(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)](2)(L)}(ClO(4))(4) (3: L = dpppda; 4: L = dppeda). Analogous reactions of 1 or [(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)(MeCN)(2)](PF(6))(2) (2) with two N,P mixed ligands, N,N-bi(diphenylphosphanylmethyl)-2-aminopyridine (bdppmapy) and N-diphenylphosphanylmethyl-4-aminopyridine (dppmapy), afforded two monocyclic clusters {[(η(5)-C(5)Me(5))(2)Mo(2)(μ(3)-S)(4)Cu(2)](2)(L)(2)}X(4) (5: L = bdppmapy, X = ClO(4); 6: L = dppmapy, X = PF(6)). Compounds 3-6 were fully characterized by elemental analysis, IR spectra, UV-vis spectra, (1)H and (31)P{(1)H} NMR spectra, ESI-MS and single-crystal X-ray crystallography. In the tetracations of 3-6, two cubane-like [Mo(2)(μ(3)-S)(4)Cu(2)] cores are linked either by one dpppda or dppeda bridge to form a bicyclic structure or by a pair of bdppmapy or dppmapy bridges to afford a monocyclic structure. The third-order nonlinear optical (NLO) properties of 1 and 3-6 in MeCN were also investigated by femtosecond degenerate four-wave mixing (DFWM) technique with a 50 fs pulse width at 800 nm. Compounds 3-6 exhibited enhanced third-order NLO performances relative to that of 1.     

η2-dithiomethyliron(II) ionic complexes. Evidence for a strong dependence on the nature of the trans-phosphorus ligands bonded to iron

Cationic η²-dithiomethyliron(II) complexes have been made by alkylation of the uncoordinated sulfur atom of Fe(CO)₂[η²-CS₂](L)₂. Surprisingly, only when the phosphorus ligands L are strong donors (PMe₃, PMe₂Ph) does coordination of iodide take place to give the neutral Fe(η²-CS₂CH₃)(I)(CO)(L)₂ derivatives. The ¹³C NMR spectra of the latter at 215 K indicated the presence of both isomers when L was PMe₂Ph. Reaction with iodine under carbon monoxide regenerated the cationic precursor.     

Triply-bridged Dicopper(Ⅰ)Complex of Bis(diphenylphosphino)acetylene with a Helical Coordination Cage

<正>Self-organization of copper (I) ion with bridging ligand bis(diphenylphosphino)-acetylene resulted in the isolation of a dinuclear copper ( I ) complex [Cu2(μ-Ph2PC≡ CPPh2)3(MeCN)2](ClO4)2·Et2O. Structural analysis indicated the existence of a helical coordination cage, in which two copper (I) atoms are bridged triply by the linear diphosphine Ph2PC≡CPPh2 with the CuACu separation of 6.231 A. The copper (I) atom is in an approximately tetrahedral environment with a NP3 coordination chromophore. The complex crystallizes in the triclinic, space group P 1 with a = 13.8456(2), b = 16.6010(1), c = 18.9215(3) A, α = 98.289(1), β = 91.232(1), γ = 106.496(1)°, V = 4117.60(9) A3, Z = 2, C86H82Cl2N2O9P6Cu2, Mr= 1659.37, Dc= 1.338 g/cm3, F(000) = 1708, μ = 0.754 mm-1, the final R = 0.0688 and wR = 0.1940 for 11692 reflections with I>2σ(I).     

Synthesis and reactivity of a transition metal complex containing exclusively TEMPO ligands: Ni(η2-TEMPO)2

The reaction of Ni(COD)(2) with two equivalents of the TEMPO radical at 68 °C affords the 16 e(-) "bow-tie" complex Ni(η(2)-TEMPO)(2), 1, in 78% yield. Compound 1 reacts with tert-butyl isocyanide and phenylacetylene at room temperature to yield the 16 e(-) distorted square planar nickel complexes Ni(η(2)-TEMPO)(η(1)-TEMPO)(CN(t)Bu), 2, and Ni(η(2)-TEMPO)(η(1)-TEMPOH)(CCPh), 4, respectively. The facile reactivity of 1 is aided by the transition of the TEMPO ligand from an η(2) to η(1) binding mode. Complex 4 is an unusual example of hydrogen atom transfer from phenylacetylene to a coordinated TEMPO ligand.