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31.
Abstract  Monoclinic crystals of [Cu2(μ-I)2(PPh3)2(μ-N, S-pymSH)] · CH3CN) (1), were obtained by equimolar reaction of copper(I) iodide with pyrimidine-2-thione (pymSH), followed by the addition of triphenylphosphine (PPh3) in acetonitrile. Crystal data for 1: space group P21, Z = 2, a = 9.896, b = 18.378, c = 11.703 ?, β = 101.73°. It has an iodo-bridged Cu(μ-I)2Cu core and the pyrimdine-2-thione binds to both Cu centers via N, S-bridging across the Cu(μ-I)2Cu core. This N, S-bridging, a rare coordination mode for pyrimidine-2-thione, leads to a short Cu···Cu separation of 2.675(2) ? (sum of van der Waals radius of Cu atoms, 2.80 ?). The geometry around each Cu center is distorted tetrahedral with angles varying in the range, ca. 102–119°. Copper(I) chloride and bromide also yielded monoclinic crystals of S-bonded tetrahedral monomers, [CuBr(pymSH)(PPh3)2] 2 and [CuCl(pymSH)(PPh3)2] 3. Crystal data for 2: space group P21/n, Z = 8, a = 12.825, b = 43.122, c = 13.396 ?, β = 90.79°. Crystal data for 3: space group P21/c, Z = 4, a = 14.340, b = 10.111, c = 24.200 ?, β = 94.36°. Compound 2 has two crystallographically independent molecules in crystal lattice. The 31P NMR spectrum of 1 showed two signals for PPh3 ligands bonded to two Cu centers with different coordination cores: CuI2PN and CuI2PS. Both 2 and 3 showed one signal each for PPh3 in their 31P NMR spectra. Graphical abstract  Reaction of copper(I) iodide with pyrimidine-2-thione and triphenylphosphine formed monoclinic crystals of dimer 1 with unusual N, S-bridging across Cu(μ2-I)2Cu core.   相似文献   
32.
The sulfur of acetophenone thiosemicarbazone {(Ph)(Me)C=N-NH-C(=S)NH(2); Haptsc} and two iodine atoms form an unusual heterobridge in the dinuclear complex [(Ph(3)P)Cu(mu-I)(2)(mu-S-Haptsc)Cu(PPh(3))] (1), leading to a short Cu--Cu distance of 2.504(1) Angstrom. This uncommon heterobridging is attributed to the presence of a methyl substituent at the Schiff base C2 carbon atom of the acetophenone thiosemicarbazone.  相似文献   
33.
Copper(I) halides with triphenyl phosphine and imidaozlidine‐2‐thiones (L ‐NMe, L ‐NEt, and L ‐NPh) in acetonitrile/methanol (or dichloromethane) yielded copper(I) mixed‐ligand complexes: mononuclear, namely, [CuCl(κ1‐S‐L ‐NMe)(PPh3)2] ( 1 ), [CuBr(κ1‐S‐L ‐NMe)(PPh3)2] ( 2 ), [CuBr(κ1‐S‐L ‐NEt)(PPh3)2] ( 5 ), [CuI(κ1‐S‐L ‐NEt)(PPh3)2] ( 6 ), [CuCl(κ1‐S‐L ‐NPh)(PPh3)2] ( 7 ), and [CuBr(κ1‐S‐L ‐NPh)(PPh3)2] ( 8 ), and dinuclear, [Cu21‐I)2(μ‐S‐L ‐NMe)2(PPh3)2] ( 3 ) and [Cu2(μ‐Cl)21‐S‐L ‐NEt)2(PPh3)2] ( 4 ). All complexes were characterized with analytical data, IR and NMR spectroscopy, and X‐ray crystallography. Complexes 2 – 4 , 7 , and 8 each formed crystals in the triclinic system with P$\bar{1}$ space group, whereas complexes 1 , 5 , and 6 crystallized in the monoclinic crystal system with space groups P21/c, C2/c, and P21/n, respectively. Complex 2 has shown two independent molecules, [(CuBr(κ1‐S‐L ‐NMe)(PPh3)2] and [CuBr(PPh3)2] in the unit cell. For X = Cl, the thio‐ligand bonded to metal as terminal in complex 4 , whereas for X = I it is sulfur‐bridged in complex 3 .  相似文献   
34.
Ruthenium(II) Complexes containing pyrimidine‐2‐thiolate (pymS) and bis(diphenylphosphanyl)alkanes [Ph2P–(CH2)m–PPh2, m = 1, dppm; m = 2, dppe; m = 3, dppp; m = 4, dppb] are described. Reactions of [RuCl2L2] (L = dppm, dppp) and [Ru2Cl4L3] (L = dppb) with pyrimidine‐2‐thione (pymSH) in 1:2 molar ratio in dry benzene in the presence of Et3N base yielded the [Ru(pymS)2L] complexes (pymS = pyrimidine‐2‐thiolate; L = dppm ( 1 ); dppp ( 3 ); dppb ( 4 )). The complex [Ru(pymS)2(dppe)] ( 2 ) was indirectly prepared by the reaction of [Ru(pymS)2(PPh3)2] with dppe. These complexes were characterized using analytical data, IR, 1H, 13C, 31P NMR spectroscopy, and X‐ray crystallography (complex 3 ). The crystal structure of the analogous complex [Ru(pyS)2(dppm)] ( 5 ) with the ligand pyridine‐2‐thiolate (pyS) was also described. X‐ray crystallographic investigation of complex 3 has shown two four‐membered chelate rings (N, S donors) and one six‐membered ring (P, P donors) around the metal atom. Compound 5 provides the first example in which RuII has three four‐membered chelate rings: two made up by N, S donor ligands and one made up by P, P donor ligand. The arrangement around the metal atoms in each complex is distorted octahedral with cis:cis:trans:P, P:N, N:S, S dispositions of the donor atoms. The 31P NMR spectroscopic data revealed that the complexes are static in solution, except 2 , which showed the presence of more than one species.  相似文献   
35.
Complexes of pyrrole‐2‐carbaldehyde thiosemicarbazones, [(C4H4N4)(H)C2=N3–N2(H)–C1(=S)–N1HR; R = Ph, H2L1; Me, H2L2; H, H2L3] with nickel(II) and palladium(II) are described. The reaction of nickel(II) acetate with H2L1 in methanol in 1:1 molar ratio yielded a complex of composition, [Ni(κ2‐N3,S‐HL1)2] ( 1 ). Likewise reaction of NiCl2 with H2L2 in 1:1 molar ratio in acetonitrile in the presence of triethylamine base followed by the addition of pyridine did not yield the anticipated [Ni(κ3‐N4,N3,S‐L2)(py)] complex, moreover a bis‐square‐planar complex, [Ni(κ2‐N3,S‐HL2)2] ( 2 ) was formed. However, in the presence of bipyridine (bipy), it yielded the addition product, [Ni(κ2‐N3,S‐HL2)22‐N, N‐bipy)] ( 3 ). Reaction of PdCl22‐P, P–PPh2–CH2–PPh2) with H2L3 in toluene in the presence of triethylamine has yielded a complex of stoichiometry, [Pd(κ3‐N4,N3,S–L3)(κ1‐P–PPh2–CH2–P(O)Ph2] ( 4 ). The ligands (HL1) and (HL2) are chelating to NiII metal atom as anions binding through N3,S‐donor atoms with pendant pyrrole groups, and (L3)2– is chelating to the PdII metal atom as dianion through N4,N3,S‐donor atoms (pyrrole is N4‐bonded). Fourth site in 4 is bonded to one P‐donor atom of PPh2–CH2–P(O)Ph2, whose pendant –PPh2 group involves auto oxidation to –P(O)PPh2 during reaction. These complexes were characterized using analytical data, IR, NMR (1H, 31P) spectroscopy and X‐ray crystallography. Complexes 1 , 2 , and 4 have square‐planar arrangement, whereas complex 3 is octahedral.  相似文献   
36.
Reactions of copper(I) halides with a series of thiosemicarbazones, namely, benzaldehyde thiosemicarbazone (R1R2CN–NH–C(S)–NH2, R1 = Ph, R2 = H; Hbtsc), 2-benzoylpyridine thiosemicarbazone (R1 = Ph, R2 = py; Hbpytsc), and acetone thiosemicarbazone (R1 = R2 = Me; Hactsc), in the presence of PPh3 has formed dimeric complexes, viz. sulfur bridged [Cu2(μ-S-Hbtsc)2Br2(PPh3)2]·2H2O (1), iodo-bridged [Cu2(μ-I)21-S-Hbtsc)2(PPh3)2] (2), and heterobridged [Cu23-S,N3-Hactsc)(η1-Br)(μ-Br)(PPh3)2] (3), as well as mononuclear complexes [CuX(η1-S-Hbpytsc)(PPh3)2]·CH3CN (X = Br, 4; Cl, 5). Complexes 1, 2, 4 and 5 involve thiosemicarbazone ligands in η1-S bonding mode while in compound 3, ligand acts in N3, S-chelation-cum-S-bridging mode (μ3-S,N3 mode). The intermolecular interactions such as, N2H?X, HN1H?X (X = S, Br, Cl), CH?π interactions lead to 2D networks. All the complexes have been characterized with the help of elemental analyses, IR, 1H, and 31P NMR spectroscopy, and single crystal X-ray crystallography. The role of a solvent in alteration of nuclearity and bonding modes of complexes has been highlighted.  相似文献   
37.
38.
Complexes of CuI with tertiary phosphine chalcogenides are described. CuI reacts with Ph3PS in MeCN/CH2Cl2 to form {CuI(Ph3PS)(MeCN)} and CuCl reacts with 1,2-ethylene-bis(tertiary phosphine selenide) {dpeSe2} in MeCN to yield {CuCl(dpeSe2)}. Both compounds exist as halogen-bridged centrosymmetric dimers: [Cu2(-I)2-(Ph3PS)2(MeCN)2] (1) and [Cu2(-Cl)2(dpeSe2)2] (2) respectively. Compound (1) has almost symmetric Cu—I bonds, d(Cu—I) = 2.6503(8) Å and d(Cu—I) = 2.7196(9) Å, and each Cu is further bonded to a S atom [d(Cu—S) = 2.3444(13) Å] from Ph3PS and to a N atom [d(Cu—N) = 2.030(5) Å] from MeCN. Compound (2) has unequal Cu—Cl bonds, 2.6390(19) and 2.2806(18) Å and nearly equal Cu—Se bonds [2.4042(11) and 2.4060(11) Å]. The geometry about each Cu center in both cases is distorted tetrahedral. The Cu—Cu bond distance in (2) is 3.249(2) Å as compared with 3.4141(16) Å in (1). MeCN is bonded strongly to CuI as the excess of Ph3PS failed to remove it from the coordination sphere. Compound (2) represents the first structurally characterised example of copper(I) with a bis(tertiary phosphine selenide) (dpeSe2) acting as a bridging ligand.  相似文献   
39.
The reactions of copper(I) halides with bis(diphenylselenophosphinyl)alkanes, namely Ph(2)P(Se)-(CH(2))(n)-P(Se)Ph(2) [n = 1-4], in acetonitrile are described. The ligand 1,3-bis(diphenylselenophosphinyl)propane [dppp-Se,Se] with copper(I) bromide and copper(I) iodide formed two unusual infinite coordination polymers, namely [Cu(2)Br(2)(mu(2)-dppp-Se-Se)(2)](n), 1, and [Cu(3)I(3)(mu(2)-dppp-Se,Se)(2)](n), 2. Selenium bridged dinuclear complexes, [Cu(2)Br(2)((mu(3)-dppm-Se,Se)(2)], 3, and [Cu(2)I(2)(dppm-Se,Se)(2)], 4, were formed using 1,1-bis(diphenylselenophosphinyl)methane [dppm-Se,Se]. Similarly, 1,2-bis(diphenylselenophosphinyl)ethane [dppe-Se,Se] and 1,4-bis(diphenylselenophosphinyl)butane [dppb-Se,Se] formed complexes, Cu(2)Br(2)(dppe-Se,Se)(2), 5, and Cu(2)I(2)(dppb-Se,Se), 6. These have been characterized with the help of analytical data, infrared spectroscopy, and, for compounds 1-3, X-ray crystallography. Compound 2, [Cu(3)I(3(dppp-Se,Se)(2)](n), has two dppp-Se,Se molecules coordinating to two copper(I) atoms of the dinuclear Cu(mu-I)(2)Cu core in unidentate fashion, with two pendant Ph(2)P(Se)- moieties in trans orientation, and one of these groups is coordinated to another copper(I) iodide moiety, thus forming the repeat unit (A), -CuI(mu-dppp-Se,Se)Cu(mu-I)(2)Cu(mu-dppp-Se,Se)-. This repeat unit (A) combined with another unit, and this process continued and finally formed the infinite polymer 2. In this polymer, the mononuclear CuISe(2) and dinuclear Cu(2)(mu-I)(2)Se(2) cores have distorted trigonal planar geometries around Cu centers. The Cu(2)...Cu(2)* separation of 2.643(1) A is less than twice the van der Waals radius of Cu, 2.80 A. The structure of polymer 1 is similar to that of 2, except that it has only mononuclear trigonal planar CuBrSe(2) units bridged by Se atoms of dppp-Se,Se ligand, and the repeat unit is -CuBr(mu(2)-dppp-Se,Se)CuBr(mu(2)(-)dppp-Se,Se)-. The formation of zigzag one-dimensional copper(I) coordination polymers (1 and 2), with trigonal planar copper(I) centers, provides the first examples of this type in tertiary phosphine chalcogenide chemistry. In contrast, the decrease in methylene chain length, from -(CH(2))(3)- to -(CH(2))-, resulted in chelation by the dppm-Se,Se ligand, forming CuBr(dppm-Se,Se), which dimerized via Se donor atoms and formed [Cu(2)Br(2)(mu(3)-dppm-Se,Se)(2)], 3. It has a relatively less common central kernel, Cu(mu-Se)(2)Cu, and each Cu atom is further bonded to one terminal Br and one Se atoms, and the geometry around each Cu center is distorted tetrahedral (bond angles, ca. 101-121 degrees).  相似文献   
40.
Summary Reactions of 1,1-methylene bis(diphenylphosphine oxide or sulphide) (dpmO2 or dpmS2) and 1-(diphenylphosphinoethyl)-2-diphenylphosphine sulphide (dpePS) with dihalodicarbonylruthenium(II) in EtOH gave 1:1 (L:M) complexes of stoichiometry: Ru(CO)2X2L2 (L = dpmO2, dpmS2 or dpePS; X = Cl or Br), which were characterized by elemental analysis and i.r. spectroscopy. The spectra reveal that: (a) the carbonyls occupy octahedral cis-positions, and (b) dpmS2 shows a higher coordination shift than does dpePS, probably due to the better Lewis basicity of the Ph2P moiety as compared to the Ph2P(S) moiety in the ligands. Cis-octahedral geometries are inferred from these studies.  相似文献   
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