Subtle Role of Polyatomic Anions in Molecular Construction:  Structures and Properties of AgX Bearing 2,4‘-Thiobis(pyridine) (X^- = NO₃^-, BF₄^-, ClO₄^-, PF₆^-, CF₃CO₂^-, and CF₃SO₃^-)

Abstract

Studies on the subtle effects and roles of polyatomic anions in the self-assembly of a series of AgX complexes with 2,4'-Py(2)S (X(-) = NO(3)(-), BF(4)(-), ClO(4)(-), PF(6)(-), CF(3)CO(2)(-), and CF(3)SO(3)(-); 2,4'-Py(2)S = 2,4'-thiobis(pyridine)) have been carried out. The formation of products appears to be primarily associated with a suitable combination of the skewed conformers of 2,4'-Py(2)S and a variety of coordination geometries of Ag(I) ions. The molecular construction via self-assembly is delicately dependent upon the nature of the anions. Coordinating anions afford the 1:1 adducts [Ag(2,4'-Py(2)S)X] (X(-) = NO(3)(-) and CF(3)CO(2)(-)), whereas noncoordinating anions form the 3:4 adducts [Ag(3)(2,4'-Py(2)S)(4)]X(3) (X(-) = ClO(4)(-) and PF(6)(-)). Each structure seems to be constructed by competition between pi-pi interactions of 2,4'-Py(2)S spacers vs Ag.X interactions. For ClO(4)(-) and PF(6)(-), an anion-free network consisting of linear Ag(I) and trigonal Ag(I) in a 1:2 ratio has been obtained whereas, for the coordinating anions NO(3)(-) and CF(3)CO(2)(-), an anion-bridged helix sheet and an anion-bridged cyclic dimer chain, respectively, have been assembled. For a moderately coordinating anion, CF(3)SO(3)(-), the 3:4 adduct [Ag(3)(2,4'-Py(2)S)(4)](CF(3)SO(3))(3) has been obtained similarly to the noncoordinating anions, but its structure is a double strand via both face-to-face (pi-pi) stackings and Ag.Ag interactions, in contrast to the noncoordinating anions. The anion exchanges of [Ag(3)(2,4'-Py(2)S)(4)]X(3) (X(-) = BF(4)(-), ClO(4)(-), and PF(6)(-)) with BF(4)(-), ClO(4)(-), and PF(6)(-) in aqueous media indicate that a [BF(4)(-)] analogue is isostructural with [Ag(3)(2,4'-Py(2)S)(4)]X(3) (X(-) = ClO(4)(-) and PF(6)(-)). Furthermore, the anion exchangeability for the noncoordinating anion compounds and the X-ray data for the coordinating anion compounds establish the coordinating order to be NO(3)(-) > CF(3)CO(2)(-) > CF(3)SO(3)(-) > PF(6)(-) > ClO(4)(-) > BF(4)(-).

Chemistry of coordination space of porous coordination polymers

“…After the first report of anionexchange properties in 1990 [39], a number of reports showing this function have been reported [102,131,135,140,[151][152][153][154][155][156][157][158][159][160][161][162][163]. Very recently, it was shown that anion exchange in the flexible framework could control gas-adsorption properties [164].…”

Crystal structure of bis(isocyanato-κ1N)-bis(2-(pyridin-4-ylthio)pyrazine- κ1N) zinc(II), C20H14N8S4Zn

“…The semi-rigid dipyridylsulfideand its N-positionalisomers are totally different from thel inear 4,4'-bipyridine ligand, as they showmore flexiblecoordination modesincoordinationsupramolecular assembly on accountofthe rotatableC(sp2)-S bonds and the variable C(sp2)-S-C(sp2) angle [2].Sofar,the coordination supramolecular architectureso fv arious isomeric dipyridyls ulfide ligands have beenreported [3].But, studies dealing with the unsymmetrically bent-shapedl igands containing pyridyla nd pyrazinyl moieties are rare [1,4]. Herein, we report the structure of ac omplex with theu nsymmetrical bent-shaped ligand 2-(pyridine-4-ylthio)pyrazine, am ultidentate ligand bearing a C(sp2)-S-C(sp2) fragment.…”

Crystal structure of trans-tetraaqua-bis(4,4′-sulfonyldipyridine-κN)zinc(II) diperchlorate dihydrate, C20H28Cl2ZnN4O18S2

“…Coordination chemistry of di-4-pyridylsul de and its positional isomers have been widely explored in the past decades [2][3][4]. However, only silver(I) complexes with 4-(pyridin-4-ylsul nyl)pyridine a ligand bearing an angular-SO-moiety derived from di-4-pyridylsul de were reported [5].…”