Syntheses and Structures of Blue-Luminescent Mercury(II) Complexes with 2,6-Bis(imino)pyridyl Ligands

Seven five-coordinate -bis imino pyridyl mercury complexes -Ar =CMe)(2)C5H8 HgCl2 center dot nCH(3)C Ar C6H5 n=1.5, 1; Ar=2,6-(Pr2C6H8)-Pr-i n=0,2; Ar = 2,6-Me2C6H8 n=1, 3; Ar = 2-MeC6H4 n=1, 4; Ar = -MeC6H4 n=1, 5; Ar = -Me3C6H2 n=1, 6; Ar = 2,6-Et2C6H8 n=0,7), were synthesized by reactions of the corresponding bis(imino)pyridine ligands with HgCl2 and in good yield. The structures of complexes 1-6 were determined by single-crystal X-ray diffraction. In all complexes die metal center is tridentately chelated by the ligand and further coordinated by two chlorine atoms resulting in a distorted trigonal bipyramidal geometry. All complexes have blue luminescence at room temperature in solution and the solid state. At in a CH2Cl2 solution the fluorescent emission maxima for complexes 1-7 are at lambda and nm respectively which can be attributed to ligant-centered pi ->pi transitions.