Solvent media as the driving force in the formation of one-dimensional silver(I) coordination polymers with 2-methylidene-1,3-bis(nicotinoyloxy)propane

Abstract

Two kinds of silver(I) coordination polymers consisting of the same chemical composition, [Ag(CF3SO3)(L)] [L is 2-methylidene-1,3-bis(nicotinoyloxy)propane], were synthesized and characterized by infrared (IR) and photoluminescence (PL) spectroscopy, elemental and thermal analyses, and single-crystal X-ray diffractometry; these are catena-poly[[(trifluoromethanesulfonato-κO)silver(I)]-μ-2-methylenepropane-1,3-diyl dinicotinate-κ2 N:N′], [Ag(CF3SO3)(C16H14N2O4)] n , and its chloroform monosolvate, {[Ag(CF3SO3)(C16H14N2O4)]·CHCl3} n . The X-ray crystallographic measurements revealed that the silver(I) compounds exhibit one-dimensional sinusoidal or helical molecular structures depending on the solvent used for crystallization. Self-assembly in a methanol/chloroform mixture produces the sinusoidal molecular strand, whereas recrystallization from acetonitrile medium affords a racemic mixture of the helical strands. These compounds display a fluorescence emission arising from both the ligand-centred transition and the ligand-to-metal charge transfer (LMCT) in the solid state under ambient conditions.