Self Assembly of Silver(I) Complexes Containing 1,4-Bis[(3-pyridyl)ethynyl]benzene

One-dimensional (1-D) zigzag chains of {[AgL]­(ClO4)­·0.5Et2O}n (1), {[AgL]­(OTf)·Et2O}n (2), and {[AgL]­(BF4)­·0.5CH3OH}n (3) were obtained from the reaction of AgClO4, AgCF3SO3, and AgBF4 with 1,4-bis­(pyridine-3-ylethynyl)­benzene (L), respectively, in similar reaction conditions, whereas it led to the formation of a 1-D sinusoidal chain of {[AgL(NO3)]·H2O}n (4) and a metallolocycle of [Ag2L6]­(BF4)2 (5) in a different reaction procedure for the AgNO3 and AgBF4 cases. Complexes 1–3 form 1-D zigzag chains, and every two chains are further stacked to give a pair of chains assisted by weak Ag­(I)···Ag­(I) and π···π interactions, whereas a single 1-D sinusoidal chain of 4 can only be obtained. Although the reaction is carried out in a similar reaction as 4 except that BF4– was used instead of NO3–, a metallocycle of 5 was obtained instead. It is noted that only the bridging L ligands in 5 adopt a syn conformation, whereas those in 1–4 are in an anti conformation. In this regard, this work has demonstrated the delicate effects of anions and reaction conditions on the assembly reactions of complexes 1–5. In addition, we observed a structural transformation during the heating process for 5. Although the powder X-ray diffraction pattern of 5 at 210 °C is similar to that of 3, it cannot be conclusively proven by powder X-ray diffraction studies at this moment due to the presence of some mismatches between both patterns of 5 and 3.