The two aromatic systems in the title compound, C(14)H(10)N(2)O, enclose a dihedral angle of 77.9 (1)°, and the C-O-C inter-ring bond angle is 117.6 (1)°.

Bis(triphenylsilyl)calcium [Ca(SiPh3)2(thf)] obtained in high yield as a crystalline ether adduct catalyzes the hydrosilylation of activated C-C double bonds efficiently and regioselectively.

In the crystal structure of the title compound, [Cu(C(18)H(16)N(6))(C(36)H(28)OP(2))]PF(6)·0.5CH(2)Cl(2) or [Cu(DPEPhos)(Bn-bta)]PF(6)·0.5CH(2)Cl(2) {DPEPhos = bis-[(diphenyl-phosphan-yl)phen-yl] ether and Bn-bta = 1,1'-dibenzyl-1H,1'H-4,4'-bi-1,2,3triazol-e}, the Cu atom is coordinated by two N and two P atoms of the ligands in a strongly distorted tetra-hedral environment. There are two cryst...

Renwick, .J. A . A , , Contrib. BoJce Thompsonlnst. 24,337 (1970). Renwick. J. A. A., Viti., J . P., Contrib. Boyce Thompson Inst. 23, 65 (1968). Renwick, J. A. A , , Viti., J . P., Contrib. Boyce Thompnon Inst. 24, 283 ( 1970). Silverstein, R. M. , in “Chemicals Controlling Insect Behaviour,” Beroza. M.. Ed., Academic Press, New York. N. Y., 1970, pp 21-40. Silverstein, R. M.. Brownlee, R. G.,...

The dihedral angle between the two aromatic ring systems in the title compound, C(15)H(12)N(2)O, is 85.9 (1)°; The angle at the O atom is widened to 118.2 (2)°. The quinoxalin-yloxy part of the mol-ecule lies on a mirror plane and the tolyl group is disordered over two positions about the mirror plane.

The dihedral angle between the two aromatic ring systems in the title compound, C(15)H(12)N(2)O, is 79.4 (1)°. The angle at the O atom is widened to 116.93 (9)°.

The aromatic ring systems in the title compound, C(14)H(10)N(2)O, form a dihedral angle of 63.8 (1)°, resulting in an opening up of the ether-O atom angle to 118.2 (1)°.

In the title compound, C12H9NO3, the ether C-O-C angle is 119.65 (10) degrees . The molecules are linked into sheets by a combination of C-H...O and C-H...pi(arene) hydrogen bonds, reinforced by an aromatic pi-pi stacking interaction.

*Engr. Dr. Bukola Olalekan Bolaji ([email protected]), Department of Mechatronics Engineering, Federal University of Agriculture, College of Engineering, P.M.B. 2240, Abeokuta, Nigeria.