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Flexible stents effectively relieved acute colonic obstruction secondary to malignant rectosigmoid neoplasm. Stent placement allowed patients to undergo single-stage surgery in most cases and provided palliative decompression in cases of inoperable or disseminated disease.

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Highly efficient deep‐blue fluorescent materials based on phenylquinoline–carbazole derivatives (PhQ‐CVz, MeO‐PhQ‐CVz, and CN‐PhQ‐CVz) are synthesized for organic light‐emitting diodes (OLEDs). The materials form high‐quality amorphous thin films by thermal evaporation and the energy levels can be easily adjusted by the introduction of different electron‐donating and electron‐withdrawing groups on carbazoylphenylquinoline. Non‐doped deep‐blue OLEDs that use PhQ‐CVz as the emitter show bright emission (Commission Internationale de L'Éclairage (CIE) coordinates, x = 0.156, y = 0.093) with an external quantum efficiency of 2.45%. Furthermore, the material works as an excellent host material for 4,4′‐bis(9‐ethyl‐3‐carbazovinylene)‐1,1′‐biphenyl dopant to get high‐performance OLEDs with excellent deep‐blue CIE coordinates (x = 0.155, y = 0.157), high power efficiency (5.98 lm W−1), and high external quantum efficiency (5.22%).

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Two geometric isomers of the tetrakis^-2-anilinopyridinato)dirhodium unit, [Rh2(ap)4]"+ ( = 0, 1), were synthesized by using different preparative procedures. Crystal and molecular structures were determined by single-crystal X-ray diffraction and show one complex, Rh2(apj4(NCC6H5) (lb), to have two pyridyl and two anilino nitrogens bound to each rhodium atom trans to their own kind and to have one axially bound benzonitrile. The second complex, Rh2(ap)4Cl (2a), has four pyridyl nitrogens and one chloride ion bound to one rhodium atom and has four anilino nitrogens bound to the other rhodium atom. Compound lb, C51H41N9Rh2, crystallizes in the orthorhombic space group Pbca with eight formula weights in a unit cell of dimensions a = 21.002 (7) Á, b = 17.317 (6) Á, and c = 26.028 (8) Á and refined to R = 0.063. Compound 2a, C44H36N8ClRh2, crystallizes in the monoclinic space group /2/c with four formula weights in a unit cell having dimensions a = 20.321 (5) Á, b = 9.594 (2) Á, c = 21.273 (4) Á, and ß = 111.35 (2)°, with final R = 0.031. Compound 1 (lb without axial benzonitrile) undergoes two reversible one-electron oxidations in CH2C12, 0.1 TBAP, at 0.08 and 0.82 V vs SCE. Complex 2a is reversibly reduced by one electron at -0.38 V and reversibly oxidized by one electron at 0.52 V in CH2C12. Electrochemical studies show that compound la (singly oxidized 1) forms bisadducts of Cl", CN", or CH3CN in CH2C12 solutions containing high concentrations of these ligands whereas 2a exists only as a monoadduct. The ESR spectra of la (rhombic signal with g3 split into a 1:2:1 triplet) and 2a (axial signal with g|| split into a doublet) aré consistent with the singly occupied molecular orbital (SOMO) being equally distributed on both Rh atoms in the former complex and being localized on one rhodium atom in the latter. Extended Hückel calculations were carried out on [Rh2(02CH)4]+, [Rh2((NH)2CH)4]+, and [Rh2((NH)2CH)4(L)]+, and the mechanisms for localization of the odd electron on 2a are discussed.