Synthesis and structural characterization of five copper(I) complexes of [2,3-f]-pyrazino-[1,10]phenanthroline-2,3-dicarbonitrile and triphenylphosphine

Five new copper(I) complexes containing PPh3 and C16H6N6, [Cu(PPh3)(C16H6N6)Cl]·H2O (1), [Cu(PPh3)(C16H6N6)Br]·CH3CN (2), [Cu(PPh3)(C16H6N6)I]·CH3CN (3), [Cu(PPh3)(C16H6N6)(CN)]·0.5 CH2Cl2(4) and Cu(PPh3)(C16H6N6)(SCN) (5) {PPh3 = triphenylphosphine, C16H6N6 = [2,3-f]-pyrazino-[1,10] phenanthroline-2,3-dicarbonitrile} have been synthesized for the first time. These complexes are obtained by the reactions of CuX (X = Cl, Br, I, CN, SCN) with the bidentate ligand C16H6N6 and the monodentate ligand PPh3 in the molar ratio of 1:1:1 in the mixed solvent of CH2Cl2 and CH3CN(5 ml/5 ml). They are characterized by X-ray crystallography, luminescence, IR, 1H NMR and 31P NMR. In solid state the complexes 1–5 are mononuclear with similar structures, but in solution they have different structures according to their different 1H NMR signals. All the complexes exhibit intense luminescence in solid state at room temperature.

Graphical abstractFive copper(I) complexes containing PPh3 and C16H6N6, {PPh3 = triphenylphophine, C16H6N6 = [2,3-f]-pyrazino-[1,10] phenanthroline-2,3-dicarbonitrile} have been synthesized for the first time. 1–5 are characterized by X-ray crystallography, luminescence, 1H and 31P NMR. 1–5 in the solid state exhibit intense luminescence at room temperature.Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Five Copper (I) complexes of [2,3-f]-pyrazino-1,10-phenanthroline-2,3-dicarbonitrile are reported. ► The coordination chemistry of C16H6N6 is interesting. ► 1–5 exhibit intense luminescence peaks around 450 nm in solid state. ► The intensity of the emission peaks is increased because of the ligand C16H6N6. ► The 1H and 31P NMR spectra of 1–5 are dependent on the counter anion.