title: Silver(I) double and multiple salts containing the 1,3-butadiynediide dianion: coordination diversity and assembly with the supramolecular synthon Ag4[cap]C[triple bond]C-C[triple bond]C[cap]Ag4.
abstract: A series of 13 silver(I) double and multiple salts containing 1,3-butadiynediide, C4(2-), were synthesized by dissolving the silver carbide Ag2C4 in a concentrated aqueous solution of one or more of the silver salts AgNO3, AgCF3CO2, AgC2F5CO2, AgF, AgBF4, and AgPF6. The 1,3-butadiynediide anion invariably adopts a mu4,mu4 coordination mode in these compounds, which indicates that the Ag4[cap]C[triple bond]C-C[triple bond]C[cap]Ag4 moiety can be used as a new type of metalloligand supramolecular synthon for the construction of coordination networks. Fine-tuning with various ancillary anionic ligands caused the Ag4 aggregate at each ethynide terminus to adopt a butterfly-shaped, planar, or barblike configuration, within which the silver-ethynide interactions can be classified into three types: sigma, pi, and mixed (sigma,pi). The effect of coexisting nitrile ligands and quaternary ammonium salts on supramolecular assembly with the above synthon was also explored. The hydrolysis of PF6(-) and BF4(-) led to the formation of the quadruple salt Ag2C4 x 4 AgNO3 x AgPF2O2 x Ag3PO4 and a novel (F)2(H2O)18 hydrogen-bonded tape in the triple salt Ag2C4 x 2 AgF x 10 AgC2F5CO2 x CH3CN x 12 H2O, respectively. The largest silver-ethynide cluster aggregate described to date, (C4)3@Ag18, occurs in 3 Ag2C4 x 12 AgC2F5CO2 x 5 [(BnMe3N)C2F5CO2] x 4 H2O (Bn = benzyl).
authors.affiliation: Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, China.
authors.forename: Liang
authors.initials: L
authors.lastname: Zhao
authors.forename: Miao
authors.initials: M
authors.lastname: Du
authors.forename: Thomas C W
authors.initials: TC
authors.lastname: Mak