Syntheses, Structure and Photoluminescence Properties of Silver(I) Complexes with Naphthalene Iminoimides

Three silver(I) complexes, namely [Ag(L)(NO 3 )] ∞ ( 1 ), [Ag(L) 2 (NO 3 )] ( 2 ) and [Ag(L) 2 ](BF 4 ) ( 3 ) {L = 9,10‐dihydro‐7 H ‐benzo[ de ]imidazo[2,1‐ a ]isoquinolin‐7‐one}, have been synthesized and characterized by X‐ray crystallography, elemental analyses and FTIR spectra. The counteranions in the Ag I salts and the ligand/Ag I ratio play fundamental roles in the formation of Ag I complexes having different crystal structures. The Ag I ions in 1 and 2 are both three‐coordinate, but they are two‐coordinate in 3 . Complex 1 adopts the polymeric chain‐like structure mainly bridged by nitrate anions. These chains are assembled into 2D sheets by the π–π stacking interaction of the ligands between the adjacent chains and weak intermolecular hydrogen bonds. They are further packed into 3D networks by C–H ··· O hydrogen bonds. For 2 and 3 , mononuclear silver(I) complexes are formed. Complex 2 is extended into an infinite zigzag chain with knots by the π–π stacking interactions of the ligands and further assembled by C–H ··· O interactions. However, the tetrafluoroborate anions in 3 are not coordinated but are connected by intermolecular hydrogen bonds to form an infinite molecular ladder with ligand‐supported Ag–N inner rungs. All the complexes display room‐temperature photoluminescence in the visible region, which may be assigned to ligand‐centred π–π* transitions supported by the theory calculation. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)