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A novel tetrathiafulvalene-(TTF-) fused poly(aryleneethynylene) with an acceptor main chain and donor side chains has been prepared and characterized. The EPR and UV-vis spectra show that there exists intramolecular charge transfer (CT) between the electron-rich TTF side chains and the electron-deficient main chain. The band gaps deduced from UV-vis absorption spectroscopy and electrochemical studies are 1.78 and 1.84 eV, respectively. Powder X-ray diffraction analysis indicate that the polymer forms a self-assembled π-stacking structure and the polymer takes an interdigitation packing mode. Polymer solar cell has been fabricated with the blend of the TTF-fused polymer and C 60 as the photosensitive layer. The power conversion efficiency is 0.25% under AM 1.5 simulated sun light (100 mW/cm 2 ). The intramolecular charge transfer was also confirmed by the chemical oxidation of the polymer with Fe(bpy) 3 (PF 6 ) 3 (bpy ) 2,2′-bipyridine).

Treatment of the o-hydroxyaryl imidazolinium pro-ligands (2-OH-3,5- 5), Ph (6), Mes (7), t Bu (8)]. Notably, without isolating 2, complexes 4-8 could also be obtained by one-pot, threecomponent, sequential reaction of N,N-dimethylbenzylamine, PdCl 2 , and the pro-ligands in refluxing acetonitrile in the presence of K 2 CO 3 . When the N-functional group on the NHCs is tert-butyl, the NHC in 8 adopts an abnormal binding (C4-bonding). All these complexes were fully characterized by 1 H and 13 C NMR, high-resolution mass spectrometry (HRMS), and elemental analysis. Singlecrystal X-ray diffraction analysis results further confirmed the molecular structures of 4-8 and the abnormal binding of NHC in 8. With methylaluminoxane (MAO) as cocatalyst these palladacycles showed excellent catalytic activities up to 10 7 g of PNB (mol of Pd) -1 h -1 in the addition polymerization of norbornene.

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A (ONSO)­CrCl complex-based binary catalyst for efficient ring-opening copolymerization (ROCOP) of epoxide and norbornene anhydride (NA) in a stereoselective manner to afford polymers with variable stereoisomerism is reported. The role of (ONSO)­CrCl complex on the cis/trans selectivity of resulting polyester as well as enhancement of the reaction rate has been revealed. The formation of chelates between the endo-diester unit of the polyester chain and the metal center plays a determinate role in the stereoselectivity of the cis-(endo, endo)-polyester in solution copolymerization of endo-NA with epoxides in the presence of metal complex. Additionally, the stereostructure of resulting polyester is also dependent on the polymerization method, NA type, and the bulkiness of the substituent of the formed ester units in the polyester chain. Accordingly, a proposed mechanistic pathway for the stereostructure formation of polyesters is provided.