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11.
José S. Casas Alfonso Castiñeiras Tarlok S. Lobana Agustín Sánchez José Sordo María S. García-Tasende 《Journal of chemical crystallography》2001,31(6):329-332
Cyclohexanone thiosemicarbazone (Hchtsc) crystallizes in the triclinic crystal system with space group P
(No. 2) and the following unit cell parameters: a = 6.2989(2), b = 7.9730(3), and c = 9.4118(2) Å = 79.607(3), = 85.519(2), and = 73.50(2)° V = 445.60(2) Å3, Z = 2. The lengths of the bonds C(1)–S, C(1)–N(1), C(1)–N(2), and N(2)–N(3) suggest electron delocalization in all four. The S atom is trans to N(3), and this E configuration is stabilized by intramolecular hydrogen bonding between N(3) and the N(1)H2 group. Two intermolecular hydrogen bonds involving the S atom and the N(1)–H(1b) and N(2)–H(2) groups give rise to a polymeric chain of molecule pairs. 相似文献
12.
Reaction of iron(III) chloride with 1,2-ethanebis(diphenylphosphine oxide) in an ethanol/chloroform mixture formed a 11 adduct of stoichiometry FeCl3(L-L) which has been characterized by X-ray crystallography as [FeCl2(L-L)2] [FeCl4]. The structure was solved by the heavy atom method, using MoK diffractometer data and refined by full-matrix least squares toR=0.044 for 8506 observed reflections. The coordination is slightly distorted octahedral for the cation with acis-arrangement of the chlorine atoms and a seven-membered chelate ring formation by Ph2P(O)CH2CH2P(O)Ph2 with the donor O atoms also in acis arrangement. The Fe-Cl distances are equal at 2.306(1) Å but the Fe-O distances differ significantly in each of the two ligands, (avg. 2.076(2) Å; avg. 1.975(3) Å). 相似文献
13.
Lobana Tarlok S. Paul Seema Hundal Geeta Obrai Sangeeta 《Transition Metal Chemistry》1999,24(2):202-205
Reaction of 1-hydroxypyridine-2-thione (HpyOS) in CHCl3 with Ag2CO3 suspended in CHCl3 under magnetic stirring followed by addition of PPh3 yields a product of stoichiometry: Ag(pyOS)(PPh3). The compound adopts a dimeric structure [Ag(pyOS)(PPh3)]2 (1) where each Ag atom acquires a distorted tetrahedral geometry by co-ordinating to one oxygen, two sulphur and one phosphorus atoms. The Ag2S2 core forms a parallelogram [Ag—S 2.507(1), 2.822(1)Å] with Ag—S—Ag and S—Ag—S angles of 74.8(1) and 105.2(1)°, respectively. 相似文献
14.
15.
Lobana TS Khanna S Butcher RJ 《Dalton transactions (Cambridge, England : 2003)》2012,41(16):4845-4851
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. 相似文献
16.
TS ENKHBAT 《Pramana》2012,79(4):879-882
A study of bound states of the fourth-generation quarks in the range of 500?C700 GeV is presented, where the binding energies are expected to be mainly of Yukawa origin, with QCD subdominant. Near degeneracy of their masses exhibits a new ??isospin??. The production of a colour-octet, isosinglet vector meson via $q\bar q \to \omega_8$ is the most interesting. Its leading decay modes are $\pi_8^\pm W^\mp$ , $\pi_8^0Z^0$ , and constituent quark decay, with $q\bar q$ and $t\bar t'$ and $b\bar b'$ subdominant. The colour octet, isovector pseudoscalar ?? 8 meson decays via constituent quark decay, or to Wg. This work calls for more detailed study of fourth-generation phenomena at LHC. 相似文献
17.
Lobana TS Sharma R Sharma R Mehra S Castineiras A Turner P 《Inorganic chemistry》2005,44(6):1914-1921
Reaction of copper(I) iodide with pyridine-2-thione (2-SC5H4NH) and 1,2-bis(diphenylphosphino)ethane (dppe) in a CH3CN-CHCl3 mixture yielded a triangular cluster, [Cu3I3(mu2-P,P-dppe)3 (eta1-SC5H4NH)], 1. Similar reaction with 2-SC5H4NH and a series of diphosphanes, Ph2P-X-Ph2P {X = -CH2- (dppm), -(CH2)3- (dppp), -(CH2)4- (dppb), -CH=CH- (dppen)}, gave a novel iodo-bridged hexanuclear Cu(I) linear polymer,{Cu6(mu3-SC5H4NH)4 (mu2-SC5H4NH)2 (I4)(mu-I)2-}n x 2nCH3CN, 2. Reactions of copper(I) iodide/copper(I) bromide with 1,3-imidazolidine-2-thione (SC3H6N2) in a CH3CN-CHCl3 mixture yielded hexanuclear Cu(I) linear chain polymers, [{Cu6(mu3-SC3H6N2)2 (mu2-SC3H6N2)4X2 (mu-X)4}n] (X = Br, 4; I, 5). In compound 1, two iodide atoms and one dppe form the dinuclear Cu(mu2-I)2 (mu2-dppe)Cu core, and two dppe ligands bridge this core with the third Cu(I) center coordinated to 2-SC5H4NH via the S atom. The chain polymer 2 has a centrosymmetric hexanuclear central core, Cu6S6I4 (mu-I)2--, formed by dimerization of six-membered trinuclear motifs, Cu3(mu2-SC3H6N2)3I3 via (mu3-S) bonding modes of the thione ligand, and has four terminal and two bridging iodine atoms in trans-orientations. Linear chains are separated by the nonbonded acetonitrile molecules. In 4 and 5, three copper(I) bromide or copper(I) iodide moieties and three SC3H6N2 ligands combined via bridging S donor atoms to form the six-membered trinuclear Cu3(mu2-SC3H6N2)3I3 cores which polymerized via S and X atoms in a side-on fashion to form linear chain polymers, [{Cu6(mu3-SC3H6N2)2 (mu2-SC3H6N2)4X2(mu-X)4}n]. The (mu3-S) modes of bonding of neutral heterocyclic thioamides are first examples, as are trinuclear cluster and linear polymers rare examples in copper chemistry. 相似文献
18.
Reaction of copper(I) iodide with pyrrole-2-carbaldehydethiosemicarbazone (Hptsc) in a 1:1 mole ratio in MeCN, followed by addition of one mole of Ph3P, yielded a complex of empirical formula, CuI(Hptsc)(Ph3P), whose X-ray structure determination has shown that it exists as an iodo-bridged dinuclear copper(I) complex, [Cu2(-I)2(
1-S-Hptsc)2(PPh3)2](1). The central kernel, Cu(-I)2Cu forms a parallelogram with unequal Cu—I distances {Cu—I, 2.644(2), 2.707(2)Å} and bond angles {Cu—I—Cu, 70.72(7), I—Cu—I, 109.28(7)°}. Each Cu atom is further bonded to one S atom of Hptsc and one P atom of Ph3P, thus completing tetracoordination. The Cu...Cu separation of 3.097(4)Å is close to the sum of the van der Waals radius of the Cu atom, 2.80 Å. Compound (1) involves relatively strong inter-dimer hydrogen bonding via hydrazinic and pyrrole ring hydrogens with sulfur and iodine atoms respectively of the adjacent dimer {N(1)H...S#2, 2.50 Å; N(4)H...I#3, 2.91 Å}. The complex represents the first report of a copper(I) dimer with a thiosemicarbazone. 相似文献
19.
Reactions of [Cu(CH(3)CN)(4)]X (X = PF(6), BF(4)) with bis(diphenylphosphino)methane (dppm = Ph(2)PCH(2)PPh(2)) and ammonium dialkyldithiophosphates, (NH(4))[S(2)P(OR)(2)] (R = Et, (i)Pr), yield a series of novel Cu(I) polynuclear complexes, trinuclear [Cu(3)(mu-dppm)(3)(mu(3)-Cl){S(2)P(OEt)(2)}] (PF(6)) 1 and [Cu(3)(mu-dppm)(2){S(2)P(OR)(2)}(2)](PF(6)) (R = Et, 2; (i)Pr, 3), tetranuclear [Cu(4)(mu-dppm)(2) {S(2)P(OEt)(2)}(4)] 4, and hexanuclear [Cu(6)(mu-dppm)(2)(mu(4)-Cl){S(2)P(O(i)()Pr)(2)}(4)](BF(4)) 5. Similarly, the reaction of [Cu(2)(mu-L-L)(2)(CH(3)CN)(2)](PF(6))(2) (L-L, dppm, dppe = Ph(2)PCH(2)CH(2)PPh(2)) with (NH(4))[S(2)P(OR)(2)] yields dinuclear [Cu(2)(mu-dppm)(2){S(2)P(OR)(2)}(2)] 6 (R= (i)Pr, 6A; Et, 6B), trinuclear [Cu(3)(mu-dppe)(3)(mu-Cl)(2){S(2)P(O(i)Pr)(2)}] 9, and polymeric [Cu(mu(2)-dppe){S(2)P(OR)(2)}](n) (R = Et, 7; (i)Pr, 8) complexes. The formation of 1 and 5 involved the abstraction of chloride from dichloromethane when the Cu/S(2)P(OR)(2) ratio exceeded 1, but when ratio was 1:1, no Cl abstraction occurred, as in compound 4. Compound 9, however, was obtained as a 12% byproduct in the synthesis of 8 using a 1:1:1 ratio of Cu/dppe/S(2)P(O(i)Pr)(2). The chloride binds to Cu atoms in a mu(3)-Cl mode by capping one face of the Cu(3) triangle of cluster 1. A mu(4)-Cl caps a single tetragonal face of the trigonal prism of cluster 5, and in the cluster 9, two chlorides bond in mu(2)-Cl modes. Both clusters 2 and 3 exhibit the mu(3)-S mode of bonding for dtp ligands. Only cluster 5 exhibited close Cu...Cu contacts (2.997-3.0238 A). All of compounds were characterized by single-crystal X-ray diffraction and pertinent crystallographic data for 1, 5, and 9 are are follows: (1) C(79)H(76)ClCu(3)F(6)O(2)P(8)S(2), triclinic, P, a = 11.213(1) A, b = 14.142(1) A, c = 25.910(2) A, alpha = 95.328(2) degrees , beta = 99.594(2) degrees , gamma = 102.581(2) degrees , V = 3918.2(6) A(3), Z = 2; (5) C(74)H(100)BClCu(6)F(4)O(8)P(8)S(8), monoclinic, P2(1)/n, a = 25.198(4) A, b = 15.990(3) A, c = 25.421(4) A, beta = 106.027(3) degrees , V = 9845(3)A(3), Z = 4; (9) C(84)H(86)Cl(2)Cu(3)O(2)P(7)S(2), monoclinic, C2/c, with a = 24.965(3) A, b = 17.058(2) A, c = 20.253(2) A, beta = 95.351(4) degrees , V = 8587.4(17)A(3), Z = 4. 相似文献
20.
Tarlok Singh Lobana Mani Kaushal Robin Bhatia Ritu Bala Ray J. Butcher Jerry P. Jasinksi 《Acta Crystallographica. Section C, Structural Chemistry》2022,78(1):30-35
In this investigation, the crystal structures of the thio-ligands 3-formylpyridine 4-phenylthiosemicarbazone (C13H12N4S, 1 ) and 4-benzoylpyridine 4-ethylthiosemicarbazone (C15H16N4S, 2 ), and of two new coordination compounds, chlorido(3-formylpyridine 4-phenylthiosemicarbazone-κS)bis(triphenylphosphane-κP)copper(I) acetonitrile monosolvate, [CuCl(C13H12N4S)(C18H15P)2]·CH3CN, 3 , and bis(3-formylpyridine 4-ethylthiosemicarbazonato-κ2N1,S)nickel(II), [Ni(C9H11N4S)2], 4 , are reported. In complex 3 , the thio-ligand coordinates in a neutral form to the Cu atom through its S-donor atom, and in complex 4 , the anionic thio-ligand chelates to the Ni atom through N- and S-donor atoms. The geometry of complex 3 is distorted tetrahedral [bond angles 99.70 (5)–123.23 (5)°], with the P—Cu—P bond angle being the largest, while that of complex 4 is square planar, with trans-S—Ni—S and N—Ni—N bond angles of 180°. 相似文献