A new right angle-shaped ligand, 2,2′-bis(4-pyridyl)-9,9′-spirobifluorene (L), is designed and synthesized. Treatment of L with silver(I) ions leads to linear polymeric metal-organic frameworks, [Ag(L) 2 ] + (1), that feature square subunits. Single-crystal X-ray analysis reveals that [Ag(L) 2 ] + has a one-dimensional double-stranded polymeric chain comprising square grids with cavity dimensions of ca. 8 Å × 8 Å. By π-π stacking of adjacent double-stranded chains, the structure is extended into a two-dimensional (2D) layer framework with a unique quasiaperture (dimensions of ca. 14 Å × 8 Å). Each 2D layer is inclined and mutually interpenetrated, which gives rise to the three-dimensional interlocked network structure. Compound 1‚(BF 4 )(CH 3 OH) crystallizes in the monoclinic system, space group C2/c, with chemical formula C 71 H 49 N 4 OBF 4 Ag, a ) 25.709(1) Å, b ) 14.4164(6) Å, c ) 15.6865-(7) Å, β ) 109.220(2)°, and Z ) 4.

A new polymeric silver complex, [Ag(2)(L(2))(ClO(4))(2)] (L = 4,5-diazospirobifluorene), has been synthesized and shown to exhibit interesting luminescence properties in a single crystal. Structural analysis reveals a one-dimensional chain, which contains a [Ag(2)(L(2))](2+) dimer bridged with ClO(4)(-). The Ag...Ag distances are 2.776(1) and 4.575(1) A incorporated by two L ligands and by a ClO(4)(-) bridge, respectively.

Cyclometalated osmium complexes with the formulas [Os(ppy) 2(CO) 2] ( 1a, b), [Os(dfppy) 2(CO) 2] ( 2a, b), and [Os(btfppy) 2(CO) 2] ( 3a, b) have been synthesized, for which the chelating chromophores ppyH, dfppyH, and btfppyH denote 2-phenylpyridine, 2-(2,4-difluorophenyl)pyridine, and 2-(2,4-bis(trifluoromethyl)phenyl)pyridine, respectively. The isomers 1a- 3a, possessing an intrinsic C 2 rotational axis as determined by single-crystal X-ray diffraction analysis, underwent slow isomerization in solution at elevated temperature, giving the respective thermodynamic products 1b- 3b, which showed a distinctive coordination arrangement produced by a 180 degrees rotation of one cyclometalated ligand around the Os(II) metal center. In contrast to the case for 1a, b and 2a, which are inert to substitution, complexes 2b and 3b (or 3a) readily react with PPh 2Me to afford the products [Os(dfppy) 2(CO)(PPh 2Me)] ( 4) and [Os(btfppy) 2)(PPh 2Me)] ( 6), in which the incoming PPh 2Me replaced the CO located trans to the carbon atom of one cyclometalated ligand. UV-vis and emission spectra were measured, revealing the lowest excited state for all complexes as a nominally ligand-centered (3)pipi* state mixed with certain MLCT character. Introduction of the electron-withdrawing substituents on the cyclometalated chelates or replacement of one CO ligand with phosphine at the metal center increased the MLCT contribution in the first excited state, giving a broad and featureless emission with greatly enhanced quantum yields.

Supplementary Materials: Stable1. Bond Lengths (Å) and Anglse (deg) for Cd(1) and Cd(2) Coordination Spheres in complex 1 a. Stable2. Bond Lengths (Å) and Anglse (deg) for Zn(1) and Zn(2) Coordination Spheres in complex 2. Sfigure1. (a) Distorted pentagonal bipyramidal coordination sphere about Cd(1) with atom labeling scheme. (b) Distorted octahedral coordination sphere about Cd(2) with atom labeling scheme (ORTEP drawing, 50 % thermal ellipsoids). Sfigure2. Distorted octahedral coordination sphere about (a) Zn(1) and (b) Zn(2) with atom labeling scheme (ORTEP drawing, 50 % thermal ellipsoids). Stable 1. Bond Lengths (Å) and Anglse (deg) for Cd(1) and Cd(2) Coordination Spheres in complex 1 a Cd(1)−O(1) 2.569(4) Cd(2)−O(1) 2.418(4) Cd(1)−O(2) 2.363(3) Cd(2)−O(5) 2.339(4) Cd(1)−O(3) i 2.398(3) Cd(2)−O(9) ii 2.325(4) Cd(1)−O(4) i 2.431(3) Cd(2)−O(10) ii 2.319(4) Cd(1)−O(6) 2.469(4) Cd(2)−O(11) w 2.257(4) Cd(1)−O(10) 2.292(4) Cd(2)−N(2) 2.268(5) Cd(1)−N(1) 2.248(5)