Blue-luminescent/electroluminescent Zn(II) compounds of 7-azaindole and N-(2-pyridyl)-7-azaindole:: Zn(7-azaindole)2(CH3COO)2, Zn(NPA)(CH3COO)2, and Zn(NPA)((S)-(+)-CH3CH2CH(CH3)COO)2 (NPA = N-(2-pyridyl)-7-azaindole)

A new 7-azaindole zinc(II) compound, Zn(7-azaindole)(2)(CH3COO)(2) (1), a new ligand N-(2-pyridyl) -7-azaindole (NPA), and two NPA zinc(II) complexes, Zn(NPA)(CH3COO)(2) (2) and Zn(NPA)((S)-(+)-CH3CH2CH(CH3)-COO)(2) (3), have been synthesized and structurally characterized. Compound 1 has a tetrahedral geometry, whereas compounds 2 and 3 have irregular six-coordinate geometry. The NPA ligand in compounds 2 and 3 functions as a bidentate chelate to the zinc center. Compound 1 has a blue luminescence in the solution and the solid state. Compounds 2 and 3 emit a blue color in the solid state. In solution, compounds 2 and 3 are fluxional, as established by H-1 NMR experiments. Compound 1 is thermally stable, whereas compounds 2 and 3 undergo decomposition when heated in the solid state. A blue electroluminescent device using compound 1 as the emitting layer has been fabricated. Crystal data: NPA, monoclinic, P2(1)/(c), a = 13.993(5) Angstrom, b = 8.456(3) Angstrom, c = 16.886(5) Angstrom, beta = 104.666(12)degrees, V = 1932.9(11) Angstrom (3); 1, triclinic, P (1) over bar, a = 9.5114(18) Angstrom, b = 10.460(7) Angstrom, c = 11.002(3) Angstrom, alpha = 117.18(3)degrees, beta = 103.287(18)degrees, gamma = 90.94(2)degrees, V = 938.3(7) Angstrom (3); 2, monoclinic, C2/c, a = 13.234(6) Angstrom, b = 9.373(3) Angstrom, c = 13.956(7) Angstrom, beta = 113.24(3)degrees, V = 1590.7(12) Angstrom (3); 3, monoclinic, P2(1), a = 11.047(7) Angstrom, b = 15.343(9) Angstrom, c = 13.785(8) Angstrom, beta = 100.123(9)degrees, V = 2300(2) Angstrom (3).