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

Abstract

One-dimensional (1-D) zigzag chains of {[AgL]-(ClO 4 )•0.5Et 2 O} n (1), {[AgL](OTf)•Et 2 O} n (2), and {[AgL]-(BF 4 )•0.5CH 3 OH} n (3) were obtained from the reaction of AgClO 4 , AgCF 3 SO 3 , and AgBF 4 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(NO 3 )]• H 2 O} n (4) and a metallolocycle of [Ag 2 L 6 ](BF 4 ) 2 (5) in a different reaction procedure for the AgNO 3 and AgBF 4 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 BF 4 − was used instead of NO 3 −, 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.

Not Too Big and Not Too Small: “Goldilocks” Anion Size for Three-Dimensional Metal–Organic Frameworks Containing Oligothiophene Dinitrile Ligands (C4H2S)n(CN)2 (n = 1, 2, 3) Bridging Silver(I) Cations

“…As a result, the N–Ag + –N bond angles are not 180° (156°, 157°, and 163° for the complexes 1 •AgSbF 6 •PhCH 3 , 2 •AgCF 3 SO 3 •PhH, and 3 •AgBF 4 •PhNO 2 , respectively). While the bent nature of the ligands 1 and 3 might naturally impart a nonlinear geometry at the silver­(I) center, ligand 2 might be expected to adopt an off-axis linear orientation with anti thiophene rings, rather than the bent orientation with syn rings found here. , The uncoordinated ligand itself does adopt the anti orientation, as do the structures of unsubstituted oligothiophenes. − In our previously published analysis, we concluded that the syn orientation in 2 •AgCF 3 SO 3 must be due to secondary interactions between the ligand and the triflate counterions. To further verify this hypothesis, we have now prepared the sterically bulky ligand 4 ; the diphenylphosphines serve to sequester the backbone hydrogen atoms.…”

“…While the bent nature of the ligands 1 and 3 might naturally impart a nonlinear geometry at the silver(I) center, ligand 2 might be expected to adopt an offaxis linear orientation with anti thiophene rings, rather than the bent orientation with syn rings found here. 20, 45 The uncoordinated ligand itself does adopt the anti orientation, 38 as do the structures of unsubstituted oligothiophenes. 46−50 In our previously published analysis, we concluded that the syn orientation in 2•AgCF 3 SO 3 must be due to secondary interactions between the ligand and the triflate counterions.…”

Conformation driven complexation of two analogous benzimidazole based tripodal ligands with Ag(I) resulting in a trigonal prism and a coordination polymer

“…It forms a trigonal prism like structure, similar to the coordination complex of 1-Me with Ag(I) 47 but in a high symmetry space group. This metallocyclic salt 59,60 is crystallized in P 6 3 /m space group with one-sixth of the cationic cage framework in the asymmetric unit. The overall cationic metallocycle, constituted of three Ag(I) ions ligated to the neutral Bim moieties of two 1-Et ligands, is forming a exhibiting syn conformation, in sixteen cases the imidazole ring of the Bim moiety is pointed inwards facing the central aromatic ring, whereas only in two structures, NASQIJ and SIJJAJ, the imidazole ring of the Bim moiety is pointed outwards, similar to the structure of 1-OMe in 1-OMe•3.6H 2 O.…”

Construction of Coordination Polymers from Semirigid Ditopic 2,2′-Biimidazole Derivatives: Synthesis, Crystal Structures, and Characterization

“…Copper and silver were selected to provide more flexible coordination geometries. The common geometries of silver­(I) complexes are linear, trigonal, and tetrahedral. − Typical coordination geometries of copper­(I or II) complexes include tetrahedral, square planar, and square pyramidal structures. − …”