XRD data and isomorphous behavior of several bridged poly(p-phenylene)s including new poly(biphenylene)s

BACKGROUND: Rigid‐rod oligomers and polymers comprising a recurring benzodiazaborole unit show high thermal stability and intriguing optical and electrochemical properties due to the expanded electron system through the BC and BN bonds in the main chain by the use of the pz orbital on boron. However, the conventional method for the preparation of these oligomers and polymers often requires polycondensation under severe conditions. In this study, we report the synthesis of oligomers comprising a recurring benzodiazaborole unit using the Stille reaction under mild conditions. In addition, we describe their chemical properties and solid‐state structures. RESULTS: The reaction of 3,3′‐diaminobenzidine with 4‐bromophenylboronic acid and benzeneboronic acid yielded 2,2′‐bis(4‐bromophenyl)‐2,3,2′,3′‐tetrahydro‐1H,1′H‐[5,5′]bi(benzo[1,3,2]diazaborolyl) (1) and 2,2′‐biphenyl‐2,3,2′,3′‐tetrahydro‐1H,1′H‐[5,5′]bi(benzo[1,3,2]diazaborolyl), respectively. Pd‐complex‐catalyzed polycondensation of 1 with bis(tributyltin) and bis(tributylstannyl)acetylene in N,N‐dimethylformamide provided oligomers comprising a recurring benzodiazaborole unit in 98 and 97% yields, respectively. CONCLUSION: The oligomers comprising a recurring benzodiazaborole unit were obtained under mild reaction conditions in high yields. The expansion of the electron system through the BC and BN bonds of the oligomers was confirmed by UV‐visible spectroscopy. The oligomers were photoluminescent in solution and electrochemically active in a film, and they assumed self‐assembled stacked structures in the solid state. Copyright © 2008 Society of Chemical Industry

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π‐conjugated polymers having diaza[12]annulene rings and aminopenta‐2,4‐dienylidene groups generated by the ring opening of pyridinium rings

Yamaguchi

Gobara

Sato

2007

J. Polym. Sci. A Polym. Chem.

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Reactions of N‐(2,4‐dinitrophenyl)pyridinium chloride with 2,5‐dimethyl‐1,4‐phenylenediamine in 1:2, 1:1.5, 1:1, and 2:1 molar ratios caused the ring opening of the pyridinium ring and thereby yielded polymers (P1–P4) consisting of 5‐(2,5‐dimethyl‐1,4‐phenylene)penta‐2,4‐dienylideneammonium chloride (unit A) and N‐2,5‐dimethyl‐1,4‐phenylene diaza[12]annulenium dichloride (unit B). The 1H NMR spectra suggested that the composition ratios of unit A to unit B in P1–P4 were 0.98:0.02, 0.94:0.06, 0.81:0.19, and 0.79:0.21, respectively. P1–P4 showed an absorption maximum (λmax) at a longer wavelength than the monomers because of the expansion of the π‐conjugation system. Films of P3 and P4 showed λmax at a considerably longer wavelength than those in solution, and this was attributable to the ordered structures of the polymers in the solid state. Powder X‐ray diffraction analysis supported the ordered structures of P3 and P4. Pellets molded from P3 and P4 exhibited a metallic luster, whereas those from P1 and P2 did not show such a luster. Cyclic voltammetry measurements indicated that P1–P4 were electrochemically active in films. The thermal stability of the polymers depended on the composition ratios of unit A to unit B. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1507–1514, 2007

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XRD data and isomorphous behavior of several bridged poly(p-phenylene)s including new poly(biphenylene)s

Cited by 5 publications

References 24 publications

Organometallic Polycondensation for Conjugated Polymers

Organometallic Polycondensation for Conjugated Polymers

Pd‐complex‐catalyzed synthesis of oligomers having a recurring benzodiazaborole unit in the main chain

π‐conjugated polymers having diaza[12]annulene rings and aminopenta‐2,4‐dienylidene groups generated by the ring opening of pyridinium rings

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