Inorganic Chemistry, Vol.42, No.6, 1928-1934, 2003
Syntheses and structures of photochromic silver(I) coordination polymers with cis-1,2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene
Five novel silver(l) coordination polymers with cis-1, 2-dicyano-1,2-bis(2,4,5-trimethyl-3-thienyl)ethene (cis-dbe) were synthesized and are characterized in this paper. Treatment of AgCF3SO3 or AgCF3CO2 with cis-dbe afforded [Ag-2(cis-dbe)(CF3SO3)(2)] (1) and [Ag2(cis-dbe)(CF3CO2)(2)] (2), and both complexes exhibit a 1-D infinite chain structure with two cyano groups and two thienyl groups of the ligand bridging four metal ions. Reaction of AgCnF2n+1CO2 with cis-dbe gave rise to an unprecedented cocrystallization of a 2-D sheet structure, [Ag-2(cis-dbe)(CnF2n+1CO2)(2)], where n = 2 (3), 3 (4), and 4 (5). Upon irradiation with 450 nm light, these five silver(l) complexes turned orange or red from yellow, and the color reverted to yellow on exposure to 560 nm light, indicative of the reversible cyclization/ring-opening reaction occurring in the crystalline phase. Furthermore, different anions gave not only the different structural dimensions but also the different photoresponsive patterns. The correlation between the crystal structures and the photochromic reactivity is discussed.