Journal of The Chemical Society-dalton Transactions最新文献

{"title":"Titanium imido complexes of pendant arm functionalised benzamidinate ligands","authors":"C. L. Boyd, A. E. Guiducci, Stuart R. Dubberley, Ben R. Tyrrell, P. Mountford","doi":"10.1039/B207184C","DOIUrl":"https://doi.org/10.1039/B207184C","url":null,"abstract":"Reactions of the lithiated pendant arm functionalised benzamidinates Li{Me2NCH2CH2NC(Ph)NSiMe3} and Li{Me2NCH2CH2CH2NC(Ph)NSiMe3} with the compounds [Ti(NR)Cl2(py)3] \u0000(R = \u0000tBu, 2,6-Me2C6H3, 2,6-iPr2C6H3) afforded five-coordinate [Ti(NR){Me2NCH2CH2NC(Ph)NSiMe3}Cl] \u00001–3 and [Ti(NR){Me2NCH2CH2CH2NC(Ph)NSiMe3}Cl] \u00004–6, respectively. Reaction of [Ti(NtBu){Me2NCH2CH2CH2NC(Ph)NSiMe3}Cl] \u00004 with C6F5NH2 gave elimination of tBuNH2 and the corresponding perfluoroarylimido complex 7. The X-ray crystal structures of [Ti(NtBu){Me2NCH2CH2NC(Ph)NSiMe3}Cl] \u00001 and [Ti(N-2,6-R2C6H3){Me2NCH2CH2CH2NC(Ph)NSiMe3}Cl] \u0000(R = Me 5 or iPr 6) have been determined. Reaction of either 1 or 4 with H2N-2,6-Me2C6H3 in C6D6 afforded the corresponding arylimido compounds 2 and 5, but this route is not amenable to easy scale-up. For better evaluation of the effects of the pendant NMe2 donor group in 1–6, the bis(pyridine) compound [Ti(NtBu){MeCH2CH2NC(Ph)NSiMe3}Cl(py)2] \u00009 was prepared from Li{MeCH2CH2NC(Ph)NSiMe3} \u00008 and [Ti(NtBu)Cl2(py)3]. The compounds 1–3 with two-carbon pendant arms are quite sensitive to adventitious protonation, and the X-ray crystal structures of the products of two such reactions, namely [Ti2{Me2NCH2CH2NC(Ph)N(H)SiMe3}2(NtBu)2Cl2(μ-Cl)2] \u000010 and [Ti2(N-2,6-C6H3Me2)2Cl2(μ-O){Me2NCH2CH2NC(Ph)N(H)SiMe3}2] \u000011, have been determined. Both possess amidine ligands that show interesting intramolecular N–H⋯X (X = \u0000μ-Cl or μ-O) hydrogen bonds.","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"3 1","pages":"4175-4184"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91327477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Transition-metal imido-boroxide complexes: a structural and spectroscopic investigation of the influence of boron","authors":"Sarah C. Cole, M. Coles, P. Hitchcock","doi":"10.1039/B207277G","DOIUrl":"https://doi.org/10.1039/B207277G","url":null,"abstract":"The four coordinate compounds Mo(NR)2[OB(mes)2]2 (1, R = tBu; 2, R = Ar = 2,6-iPr2C6H3) have been obtained from the reaction of [(mes)2BOLi(Et2O)n]x with the corresponding Mo(NR)2Cl2(dme) starting material; for structural comparison, Mo(NtBu)2[OCH(mes)2]2 (3) was also synthesised. The related five-coordinate complexes Ti(NtBu)[OB(mes)2]2(py)2 (4) and Ti(NtBu)[OCH(mes)2]2(py)2 (5) were made using analogous procedures. X-Ray structural investigations of 1–5 were performed to assess the effect that the boron atom has on the metal–oxygen and metal–nitrogen(imido) bond lengths and angles. On average, both classes of compound displayed longer metal–oxygen bonds and shorter metal–nitrogen(imido) bonds for the boroxide derivatives. Spectroscopic investigation of the Δδ values for the tert-butylimido derivatives revealed that complexes incorporating the [OB(mes)2]− anion exhibit a reduction in the electron density at the imido nitrogen atom, in agreement with the observations from the solid state structures.","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"5 1","pages":"4168-4174"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78409226","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spin distribution in copper(I) phosphine complexes of verdazyl radicals","authors":"D. J. Brook, Vincent W. Abeyta","doi":"10.1039/B205923C","DOIUrl":"https://doi.org/10.1039/B205923C","url":null,"abstract":"Copper(I) forms mixed ligand coordination compounds with the stable, paramagnetic bipyridine analogue, 1,5-dimethyl-3-(2-pyridyl)-6-oxoverdazyl (pyvd) and a variety of monodentate and bidentate phosphine ligands. These compounds were characterized in solution by titration, UV-vis spectra, ESR spectra and electrospray mass spectrometry. Coordination of the phosphine gives a metal–ligand charge transfer transition in the UV-vis that is red shifted by more electron donating phosphines. ESR indicates that spin density on copper increases, both with strongly electron donating phosphines and with weakly basic phosphite ligands. This can be explained by the presence of two different orbital interactions: with more donating phosphines the interaction is predominantly through the filled copper(I) d-orbitals, but with weakly donating phosphite ligands the interaction is through an empty copper(I) p-orbital. The differing spin transfer mechanisms may have implications in the design of molecular magnetic systems.","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"36 1","pages":"4219-4223"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83663674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"New copper selenium clusters with a sulfur functionalised ligand shell","authors":"O. Fuhr, Anthony P. Meredith, D. Fenske","doi":"10.1039/B205057A","DOIUrl":"https://doi.org/10.1039/B205057A","url":null,"abstract":"We introduce two new sulfur functionalised phosphines P(C6H4SMe)3L1 and PPh2C6H4SMe L2. Using them as ligands, four new copper selenium clusters were synthesized. The compounds [Cu15Se3(SePh)9(P(C6H4SMe)3)6] \u00001, [Cu22Se6(SePh)10(PPh2C6H4SMe)8] \u00002, [Cu20Se(SePh)12(OAc)6(PPh2C6H4SMe)2] \u00003 and [Cu38Se4(SePh)24(OAc)6(PPh2C6H4SMe)4] \u00004 were characterized by single crystal X-ray analysis and demonstrate the coordination of the phosphines through the phosphorus atoms. The thiomethyl groups of the ligands are not coordinated to any metal centre, but are located on the surface of the organic shell of the cluster molecules. This may provide an opportunity for further reactions between the functionalised clusters and metal atoms or surfaces. Furthermore the inner cluster cores show arrangements of copper and selenium atoms not yet found in these kinds of compounds.","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"61 1","pages":"4091-4094"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80629805","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cyclo-[Ni(μ2-SPh)2]9 and cyclo-[Ni(μ2-SPh)2]11: new oligomeric types of toroidal nickel(II) thiolates containing geometrically unprecedented 9- and 11-membered ring systems","authors":"S. Ivanov, Michael A. Kozee, W. A. Merrill, S. Agarwal, L. F. Dahl","doi":"10.1039/B204273H","DOIUrl":"https://doi.org/10.1039/B204273H","url":null,"abstract":"Two new oligomeric types of toroidal nickel(II) monothiolate ring systems, cyclo-[Ni(SPh)2]11 \u0000(1) and cyclo-[Ni(SPh)2]9 \u0000(2), containing heretofore unknown 11-membered (n \u0000= 11) and 9-membered (n \u0000= 9) ring-geometries, respectively, are reported. Our initial isolation of 1 was as an unexpected by-product that resulted from unsuccessful attempts to produce crystalline nanostructural gold thiolate clusters from reactions of alkyl/phenyl thiols with the recently prepared nanostructural [Au16Ni24(CO)40]4− cluster. The unique architecture of 1 led to a designed preparation of it by a direct synthetic route involving reactions of PhSNa with Ni(ClO4)2 in THF or DMF. Slow addition of the reactants at low temperature afforded two crystal forms of 1: namely, the previously isolated triclinic crystals (P) as well as solvated monoclinic crystals (C2/c) \u0000(1a). Normal mixing of the reactants at room temperature gave rise to a trigonal crystal form (P12/c) that was determined to be cyclo-[Ni(SPh)2]9 \u0000(2). The atomic arrangements and stoichiometries of both 1 and 2 were unequivocally established from low-temperature CCD area-detector X-ray diffractometry studies; particularly noteworthy is that the structures of both crystal forms of 1 possess nearly identical molecular geometries (including the phenyl-ring orientations) along with an encapsulated THF molecule. These new air-stable molecular additions to the cyclo-[Ni(μ2-SR)2]n family (with n \u0000= 4, 5, 6, and 8) are of particular stereochemical interest in that: (1) in sharp contrast to the previously known monodentate thiolate-bridged members which ideally possess regular convex Ni–S toroids, the assembled n-localized edge-fused square-planar [NiS4] subunits found in the triclinic and monoclinic crystal forms of undecanickel 1 and in the trigonal crystal form of nonanickel 2 have irregularly-shaped mixed concave/convex toroidal pseudo-C2v and pseudo-D3h ring geometries, respectively, that are geometrically unique; (2) \u00001 is the first host member of any known cyclo-[Ni(SR)2]n oligomer to have a co-crystallized solvated guest molecule (viz., THF); and (3) the observed orientations of adjacent phenyl rings attached to the highly pyramidal sulfur atoms in both 1 and 2 suggest the occurrence of weakly attractive pairwise phenyl⋯phenyl dispersion forces that are presumed to stabilize these novel nickel(II) phenylthiolate oligomers. A comparative analysis of the salient solid-state structural features of the idealized Ni–S ring geometries of the resulting entire cyclo-[Ni(SPh)2]n family (n \u0000= 4, 5, 6, 8, 9, and 11) is presented (under the assumed absence of sterically crowded R-substituents and/or abnormal packing effects). The unsymmetrical enlargement of the pseudo-threefold 9-membered ring in 2 by the formal insertion of two adjacent [Ni(SPh)2] units to give an otherwise analogous Ni–S framework of the 11-membered ring in 1 is attributed to the elongated template-geometry of the guest molecule coupled with the main","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"3 1","pages":"4105-4115"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74407579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Syntheses, characterization and redox properties of homoleptic ruthenium(II)–diphosphine and diarsine complexes: deviations from ligand additivity","authors":"Annemarie A. La Pensée, J. Bickley, S. Higgins, M. Marcaccio, F. Paolucci, S. Roffia, J. Charnock","doi":"10.1039/B206234H","DOIUrl":"https://doi.org/10.1039/B206234H","url":null,"abstract":"Homoleptic Ru(II)–diphosphine and Ru(II)–diarsine complexes, [Ru(L–L)3]2+, have been synthesized by two routes. Treatment of [RuCl2(PPh3)3] with excess ligand in EtOH gave [Ru(L–L)3]Cl2 only for L–L = 1,2-(Me2As)2C6H4 \u0000(diars) \u00001a and Me2PCH2PMe2 \u0000(dmpm) \u00002a. In the latter reaction, neutral trans-[RuCl2(dmpm–P,P′)(dmpm–P)2] \u00003 was also a product (detected by 31P{1H} NMR spectroscopy). A more widely-applicable synthesis was treatment of the halide-free starting material [Ru(dmf)6](OTf)3 \u0000(dmf = Me2NCHO; OTf = CF3SO3−) with excess ligand in EtOH. This gave the triflate salts [Ru(L–L)3](OTf)2 \u0000(L–L = diars 1b, dmpm 2b, Me2PCH2CH2PMe2 \u0000(dmpe) \u00004 and Et2PCH2CH2PEt2 \u0000(depe) \u00005. The complexes were characterized by microanalysis, infrared and electronic spectroscopies, multinuclear NMR spectroscopy, and FAB mass spectrometry. The crystal structure of [Ru(diars)3]Cl2·0.5dmf·H2O has been determined. The mean Ru–As bond length, 2.4468(15) \u0000A, is significantly longer than for typical trans-[RuII(diars)2] moieties (2.425 A; mean of 14 structures), suggesting steric crowding. X-Ray quality crystals of the diphosphine complexes were not obtained. However, Ru K-edge EXAFS measurements on [Ru(dmpe)3](OTf)2 were fitted well by a shell of six phosphorus atoms at Ru–P = 2.38(1) \u0000A, compared with 2.31 A for published structures containing trans-[RuII(dmpe)2], again indicative of steric crowding. Electrochemical studies, in extremely anhydrous media, revealed an irreversible oxidation for [Ru(L–L)3](OTf)2 assigned as Ru(II)/Ru(III), at EPAca.+2.3 V vs. ferrocene/ferrocinium. Digital simulation showed that the oxidations are kinetically slow, and the formal Ru(II)/Ru(III) potentials are around +1.8 V. This is more positive than the value predicted using published electrochemical ligand parameters (EL). The latter were checked, for diars and dmpe, by synthesizing and measuring the Ru(II)/Ru(III) redox potentials of [Ru(2,2′-bipyridine)2(L–L)](OTf)2 \u0000(L–L = dmpe 6 and diars 7). The crystal structure of 7 was determined. The mean Ru–As bond length, 2.4066(3) \u0000A, lends further support to the contention that the homoleptic cation 1 is sterically crowded. Attempts to synthesise pure samples of related complexes with monodentate phosphines (PR3) or aryldiphosphines were unsuccessful.","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"52 1","pages":"4095-4104"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78967307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel polynuclear CuII/CoII complexes constructed from one and two Cu2Co triangles with antiferromagnetic exchange coupling","authors":"V. G. Makhankova, O. Vassilyeva, V. N. Kokozay, B. Skelton, L. Sorace, D. Gatteschi","doi":"10.1039/B205389F","DOIUrl":"https://doi.org/10.1039/B205389F","url":null,"abstract":"The reaction of acetonitrile solutions of CoX2·2H2O (X = NCS, I, Br) and 2-dimethylaminoethanol (HL) with copper powder in air leads to the formation of new tri- and hexa-nuclear complexes [Cu2Co(NCS)3L3]·½CH3CN (1), [Cu2Co(μ3-OH)I2L3]2·4CH3CN (2) and [Cu2Co(μ3-OH)Br2L3]2·2CH3CN (3). X-Ray crystallographic analysis of 1 reveals a symmetrical triangular core with one Co and two Cu atoms. The amino alkoxo- and SNCS-bridges between metal centres result in copper–copper and copper–cobalt separations of 3.413(2) and 3.103(2) \u0000A, respectively. Additional intermolecular association occurs through the NCS groups bridging Co and Cu centres of adjacent complex molecules to give chains. In the solid-state structures of 2 and 3 two symmetry-related Cu2Co units are linked by amino alkoxo bridges to form a hexanuclear molecule with intermetallic distances ranging from 3.102(2)–3.260(2) \u0000(Cu⋯Co) to 3.287(3)–3.931(2) \u0000A \u0000(Cu⋯Cu). The triangular planes formed by two copper and one cobalt atoms bridged by oxygen atoms from L groups are capped by a μ3-hydroxide not found in the core of 1. The hexanuclear units show no significant intermolecular contacts in the solid state. Variable-temperature magnetic susceptibility studies performed on 1 and 2 in the temperature range 5–280 K gave satisfactory fits to the observed susceptibility data by assuming isotropic magnetic exchange interactions and using the appropriate spin Hamiltonians considering 1 as a trinuclear entity and 2 as a combination of two trinuclear entities. An antiferromagnetic spin exchange operates in the Cu2Co units of both complexes [JCuCu \u0000= 40.1(4) \u0000(1), 48.7(9) \u0000(2); JCuCo \u0000= 141(2) \u0000(1), 86.2(1.3) cm−1 \u0000(2)] while a weak ferromagnetic coupling is active between Cu and Co ions from different trinuclear entities in 2 \u0000(JCuCo′ \u0000= \u0000−8.0(4) cm−1).","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"21 1","pages":"4253-4259"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84864730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Novel heterometallic Cd/Cu complexes prepared using zerovalent copper: control of the nuclearity and structural diversity by halide counterions","authors":"E. A. Vinogradova, O. Vassilyeva, V. N. Kokozay, B. Skelton, Jens K. Bjernemose, P. Raithby","doi":"10.1039/B205917G","DOIUrl":"https://doi.org/10.1039/B205917G","url":null,"abstract":"Three kinds of CdII/CuII compounds of different nuclearity: tetranuclear [Cd2Cu2I4L4(dmso)2] 1, pentanuclear [Cd2Cu3Br6L4(dmso)2] 2 and hexanuclear [Cd4Cu2Cl6L6(H2O)2] 3, have been synthesised by the reaction of zerovalent copper and cadmium halides with non-aqueous (dmso, CH3CN) solutions of 2-dimethylaminoethanol (HL) in air. The choice of counteranion in the initial cadmium salt provides a useful method of altering the nuclearity and structure of the heterometallic Cd/Cu complexes. Crystallographic investigations reveal that 1 has a centrosymmetric tetranuclear structure with a zig-zag Cd–Cu–Cu–Cd skeleton. The molecular structure of 2 consists of a pentanuclear centrosymmetric core in which four metal atoms are linked together by bridging oxygen atoms of L groups and bromide anions to form a parallelogram Cu–Cd–Cu–Cd centred on the fifth Cu. The hexanuclear complex 3 is made up of two symmetry-related units with triangular CuCd2 cores linked by amino alkoxo bridges, involving cadmium centres of both units.","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"1 1","pages":"4248-4252"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72994656","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Structures and properties of 6-aryl substituted tris(2-pyridylmethyl)amine transition metal complexes","authors":"Zhicong He, D. Craig, Stephen B. Colbran","doi":"10.1039/B207406K","DOIUrl":"https://doi.org/10.1039/B207406K","url":null,"abstract":"A series of metal(II) complexes of [6-(2′,5′-dimethoxyphenyl)-2-pyridylmethyl]bis(2-pyridylmethyl)amine (L) have been prepared. X-Ray crystal structures have been determined for L and its metal(II) chloride complexes for Mn, Fe, Co, Ni, Cu and Zn and the results compared. The preparation and crystal structure of the unusual carbonato-bridged copper-tetramer [Cu4(L)4(CO3)2][BF4]4·5.2H2O is also described. The solution-state structures of the complexes are deduced from their physicochemical and spectroscopic properties. The Zn(II) complex, [ZnCl2(L)], shows inversion about the ligand amine group on the NMR timescale — results from a variable temperature NMR study are presented and allow estimation of the barrier to amine inversion as 56 ± 0.5 kJ mol−1. Overall, it is found that the intramolecular steric interactions introduced by substitution of the tris(2-pyridylmethyl)amine (tpa)-skeleton by a single 6-aryl group result in significant changes to the structures and properties of the resulting metal complexes: in particular the aryl-substitution in L causes (i) a weaker ligand-field compared to tpa favouring high-spin complexes, (ii) a tendency toward lower coordination numbers, and (iii) hemilability in the Ni(II) and Cu(II) complexes — the aryl-substituted leg of the ligand (L) is coordinatively labile.","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"8 1","pages":"4224-4235"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79185576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bridging mode flexibility of 1,3-dithiacyclohexane in silver(I) co-ordination polymers","authors":"L. Brammer, C. S. Rodger, A. Blake, N. R. Brooks, N. Champness, John W. Cunningham, P. Hubberstey, S. Teat, Claire Wilson, M. Schröder","doi":"10.1039/B205278B","DOIUrl":"https://doi.org/10.1039/B205278B","url":null,"abstract":"Co-ordination polymers with Ag∶1,3-dithiane molar ratios of 1∶1, {[Ag2(1,3-dithiane)2][X][Y]}∞(X = Y = NO3, 1; X = Y = PF6, 2; X = Y = BF4, 3; X = BF4, Y = Cl, 4; X = Y = NO2, 5, and 2∶1, {[Ag2(1,3-dithiane)(SO4)(H2O)2]·H2O}∞6, the extended structures of which are 1-D chains and 2-D sheets, respectively, have been synthesised and structurally characterised. The recurrent structural motif is the [Ag2(μ-1,3-dithiane)2]2+ cationic dimer in which two chair-conformation 1,3-dithiane molecules act as two-connecting units to bridge two Ag(I) centres. In 1, 2, and 6, the dimers are linked into near-linear chains by pairs of bridging anions via formation of an Ag2X2 rhomboid dimer. In 3, instead of forming the Ag2X2(X = F) rhomboid dimer, two [BF4−] anions form μ2-F,F′-bridges which support weak Ag–S interactions between cations to give a saw-tooth chain structure. This extra Ag–S contact makes the 1,3-dithiane a three-connecting unit. In 4 and 5, the Ag(I) centres of the cationic dimer are bridged not only by two 1,3-dithiane molecules but also by a Cl− or NO2− anion, respectively, to give [Ag2(μ-1,3-dithiane)2(μ2-Cl)]+(4) and [Ag2(μ-1,3-dithiane)2(μ2-O,O′-NO2)]+(5). In 4, the Cl− anion acts as a μ4-bridge to link three [Ag2(μ-1,3-dithiane)2]2+ moieties and generate a zig-zag chain. In 5, one oxygen of the bridging NO2− anions acts as a μ2-bridge to link two [Ag2(μ-1,3-dithiane)2]2+ dimers and generate a saw-tooth chain. Although the chains in 1, 2, 3 and 5 are uncharged, that in 4 is cationic and that in 6 is anionic. Charge balance in 4 is maintained by a non-co-ordinated [BF4−] anion; that in 5 is maintained by ‘Ag(H2O)2+’, the co-ordination polyhedron of which is completed by sulfur donors from separate 1,3-dithiane molecules, which thus act as four-connecting units, and by two oxygens of separate SO42− anions to give a two-dimensional sheet structure.","PeriodicalId":17317,"journal":{"name":"Journal of The Chemical Society-dalton Transactions","volume":"61 1","pages":"4134-4142"},"PeriodicalIF":0.0,"publicationDate":"2002-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90996583","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}