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Binaphthyl Units (binaphthyl + unit)
Selected AbstractsChiral C2 -Symmetric Ligands Containing Two Binaphthyl Units Linked by 2,2,-Bipyridyl Bridge in Asymmetric Catalysis.CHEMINFORM, Issue 27 2005Xiao-Li Bai Abstract For Abstract see ChemInform Abstract in Full Text. [source] High-Performance Membranes from Polyimides with Intrinsic Microporosity,ADVANCED MATERIALS, Issue 14 2008Bader S. Ghanem Membranes with high permeability to gases are formed from polyimides with rigid backbones that incorporate a spiro-centre (see figure). A route to this new range of high-free-volume polyimides is demonstrated, and exceptional performance is obtained for a polymer containing a dimethyl binaphthyl unit. [source] A Click Approach to Chiral-Dendronized Polyfluorene DerivativesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 23 2007Zi-Tong Liu Abstract A new kind of chiral-dendronized binaphthyl-containing polyfluorene derivatives has been synthesized through "click chemistry" efficiently. The resulting copolymers exhibited desirable properties, such as excellent solubility, good thermal stability, and considerably high molecular weights. The photophysical properties of the copolymers were investigated in details, and the results indicated that the combination of chiral binaphthyl unit and bulky dendron could effectively suppress intermolecular packing and aggregation. In addition, the investigation of circular dichroism behavior of these chiral-dendronized copolymers showed a strong Cotton effect at long wavelength (373,379 nm), indicating that the chirality of the binaphthyl units was transferred to the whole polyfluorene backbone. [source] Sulfonated poly(ether sulfone)s with binaphthyl units as proton exchange membranes for fuel cell applicationJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 21 2009Kazuya Matsumoto Abstract Sulfonated poly(ether sulfone)s containing binaphthyl units (BNSHs) were successfully prepared for fuel cell application. BNSHs, which have very simple structures, were easily synthesized by postsulfonation of poly(1,1,-dinaphthyl ether phenyl sulfone)s and gave tough, flexible, and transparent membranes by solvent casting. The BNSH membranes showed low water uptake compared to a typical sulfonated poly(ether ether sulfone) (BPSH-40) membrane with a similar ion exchange capacity (IEC) value and water insolubility, even with a high IEC values of 3.19 mequiv/g because of their rigid and bulky structures. The BNSH-100 membrane (IEC = 3.19 mequiv/g) exhibited excellent proton conductivity, which was comparable to or even higher than that of Nafion 117, over a range of 30,95% relative humidity (RH). The excellent proton conductivity, especially under low RH conditions, suggests that the BNSH-100 membrane has excellent proton paths because of its high IEC value, and water insolubility due to the high hydrophobicity of the binaphthyl structure. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5827,5834, 2009 [source] A Click Approach to Chiral-Dendronized Polyfluorene DerivativesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 23 2007Zi-Tong Liu Abstract A new kind of chiral-dendronized binaphthyl-containing polyfluorene derivatives has been synthesized through "click chemistry" efficiently. The resulting copolymers exhibited desirable properties, such as excellent solubility, good thermal stability, and considerably high molecular weights. The photophysical properties of the copolymers were investigated in details, and the results indicated that the combination of chiral binaphthyl unit and bulky dendron could effectively suppress intermolecular packing and aggregation. In addition, the investigation of circular dichroism behavior of these chiral-dendronized copolymers showed a strong Cotton effect at long wavelength (373,379 nm), indicating that the chirality of the binaphthyl units was transferred to the whole polyfluorene backbone. [source] Self-assembly of multinuclear complexes with enantiomerically pure chiral binaphthoxy imine ligands: Effect of the alkyl spacer connecting two binaphthyl units on the metal bindingCHIRALITY, Issue 9 2006Takeshi Maeda Abstract Metal complexing behavior of enantiomerically pure ,,,-diiminoalkanes possessing the two terminal binaphthyl units (L1 and L2) was studied. The ligands L1 and L2 were prepared by the reaction of optically pure 2,-butoxy-3-formyl-2-hydroxy-1,1,-binaphthyl with propane and pentane diamines. Reactions of L1 and L2 with equimolar amount of Cu(OAc)2 afforded quantitatively multinuclear complexes 1. The structure of 1 was confirmed by MALDI,TOF MS spectroscopy, X-ray single-crystal-structure analysis, and UV/vis and CD spectroscopic analyses. The reaction of L1 having a 1,3-propanediyl spacer resulted in the formation of a self-assembled product, which was assigned as enantiopure trinuclear circular helicate 1a, while the ligand having a 1,5-pentanediyl spacer L2 gave a different self-assembled product, dinuclear side-by-side complex 1b. The circular dichroism (CD) spectrum of 1a in solution showed intense Cotton effects in both the ,,,* transition of the naphthalene units and the LMCT region of the N,O -chelate moieties. The CD spectrum of 1b was completely different from that of 1a; in particular the Cotton effects in the LMCT region were very weak, contrary to those of 1a. These results suggest that 1a retains some chirality induced on the N,O -chelating moieties even in solution, while the induced chirality on the N,O -chelating moieties in 1b is not very significant, being consistent with the consequences of the X-ray single-crystal-structure studies. Chirality, 2006. © 2006 Wiley-Liss, Inc. [source] | |||||||||||||