Synthesis of the trans-bidentate ligand 1,2-bis(quinolin-2-ylethynyl)benzene and the X-ray crystal structure of its complex with palladium(II) chloride

A new trans -bidentate ligand, 1,2-bis(quinolin-2-ylethynyl)benzene, was synthesized and coordinated to PdCl 2 . The structure of the acetonitrile solvate of this species was determined by single-crystal X-Ray diffraction. The complex crystallizes in the orthorhombic space group Ibam , with a = 25.0726(18) Å, b = 11.7373(6) Å, and c = 18.9700(10) Å in a layered structure. When bound to 1,2-bis(quinolin-2-ylethynyl)benzene, the Pd(II) metal center displays a rectangular planar geometry. This coordination complex was compared to PdCl 2 -coordinated 1,2-bis(2-pyridylethynyl)benzene, a previously reported trans -bidentate ligand. Structural comparison of these two species indicated that the binding pocket for these two trans -bidentate ligands are similar, though the 1,2-bis(quinolin-2-ylethynyl)benzene ligand is somewhat more planar.