1,2-Bis(2-pyridylethynyl)benzene, a Novel Trans-Chelating Bipyridyl Ligand. Structural Characterization of the Complexes with Silver(I) Triflate and Palladium(II) Chloride

The design, synthesis, and complexation characteristics of the bipyridyl ligand 1,2-bis-(2-pyridylethynyl)benzene
are described. The X-ray crystallographic characterization of the 1:1 complexes of 1,2-bis(2-pyridylethynyl)benzene with silver(I) triflate and palladium(II) chloride are described. In the X-ray crystal structure of the silver(I) triflate complex the ligand is essentially planar with negligible distortion compatible with a good fit of the
cation in the “cavity” between the pyridine N atoms. Indeed the silver center is almost linear with the N(1)−Ag(1)−N(2) angle of 177.02(10)°. The ligand is also essentially planar in the palladium(II) chloride complex
with square planar coordination about the palladium with the N(1)−Pd(1)−N(2), Cl(2)−Pd(1)−Cl(2), and N(1)−Pd(1)−Cl(2) angles at 179.53(7), 177.17(2), and 90.52(5)°, respectively.