Preparation and solid-state characterization of mixed-ligand coordination/organometallic oligomers and polymers of copper(I) and silver(I) using diphosphine and mono- and diisocyanide ligands

The dimers Cu(2)(dppm)(2)(CN-t-Bu)(3)](BF(4))(2) and Ag(2)(dppm)(2)(CN-t-Bu)(2)](X)(2) (X(-) = BF(4)(-), ClO(4)(-)) and the coordination polymers M(diphos)(CN-t-Bu)(2)]BF(4)](n) (M = Cu, Ag; diphos = bis(diphenylphosphino)butane (dppb), bis(diphenylphosphino)pentane (dpppen), bis(diphenylphosphino)hexane (dpph)), Ag(2)(dppb)(3)(CN-t-Bu)(2)](BF(4))(2)](n), and Ag(dpppen)(CN-t-Bu)]BF(4)](n) have been synthesized and fully characterized as model materials for the mixed bridging ligand polymers which exhibit the general formula M(diphos)(dmb)]BF(4)](n) (M = Cu, Ag; dmb = 1,8-diisocyano-p-menthane) and Ag(dppm)(dmb)]ClO(4)](n). The identity of four polymers (Ag(dppb)(CN-t-Bu)(x)]BF(4)](n) (x = 1, 2), Ag(2)(dppb)(3)(CN-t-Bu)(2)](BF(4))(2)](n), Ag(dppm)(dmb)]ClO(4)](n)) and the two dimers has been confirmed by X-ray crystallography. The structure of Ag(dppm)(dmb)]ClO(4)](n) exhibits an unprecedented 1-D chain of the type "Ag(dmb)(2)Ag(dppm)(2)(2+)](n)", where d(Ag(.)Ag) values between tetrahedral Ag atoms are 4.028(1) and 9.609(1) A for the dppm and dmb bridged units, respectively. The Ag(dppb)(CN-t-Bu)(x)]BF(4)](n) polymers (x = 1, 2) form zigzag chains in which the Ag atoms are tri- and tetracoordinated, respectively. The Ag(2)(dppb)(3)(CN-t-Bu)(2)](BF(4))(2)](n) polymer, which is produced from the rearrangement of Ag(dppb)(CN-t-Bu)(2)]BF(4)](n), forms a 2-D structure described as a "honeycomb" pattern, where large Ag(dppb)(+)](6) macrocycles each hosting two counterions and two acetonitrile guest molecules are observed. Properties such as glass transition temperature, morphology, thermal decomposition, and luminescence in the solid state at 293 K are reported. The luminescence bands exhibit maxima between 475 and 500 nm with emission lifetimes ranging between 6 and 55 micros. These emissions are assigned to a metal-to-ligand charge transfer (MLCT) of the type M(I) --> pi(NC)/pi(PPh(2)).