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11.
As a self-doped conducting polyaniline bearing phosphonic acid, poly(2-methoxyaniline-5-phosphonic acid) (PMAP) was synthesized via oxidative polymerization of 2-methoxyaniline-5-phosphonic acid. The pyridinium salt of thus-obtained PMAP was water-soluble and its film exhibited conductivity.  相似文献   
12.
A naturally occurring 1,1'-biphenanthrene, blestriarene C (1), was prepared in 13 steps and 30% overall yield. The key steps are the ester-mediated nucleophilic aromatic substitution on 2,6-di-tert-butyl-4-methoxyphenyl 5-isopropoxy-2-methoxybenzoate (4) by 2-methoxy-4-methoxymethoxy-6-methylphenylmagnesium bromide (5) and a novel intramolecular cyclization of the resulting 4-isopropoxy-2'-methoxy-4'-methoxymethoxy-6'-methylbiphenyl-2-carboxylic ester 14 to 7-isopropoxy-4-methoxy-2-(methoxymethoxy)phenanthren-9-ol (15). The racemic blestriarene C was optically resolved by chiral HPLC on a preparative scale to give several 10-mg yields of both the enantiomers in up to 95% ee. The absolute stereochemistry was determined to be S(a)-(-) by the axial chirality recognition method, which was based on the stereospecific formation of a 12-membered cyclic diester containing two biaryl-o,o'-diyl unites joined by ester -CO(2)- linkages. The validity of the method was confirmed by an X-ray crystallographic analysis and ab initio conformational analyses of such 12-membered cyclic diesters. It was found that blestriarene C and its 7,7'-diisopropyl ether 2 underwent rapid photoracemization even under ambient light exposure.  相似文献   
13.
A naturally occurring 1,1'-biphenanthrene, blestriarene C, was prepared and its absolute stereochemistry was determined to be Sa-(-) by an empirical method, during which the compound was found to undergo rapid photoracemization even under ambient light exposure.  相似文献   
14.
Sumanenemonoone imine compounds bridged by a redox‐active π‐conjugated unit on the basis of the conversion between 1,4‐phenylenediamine and 1,4‐benzoquinonediimine were synthesized and characterized. The stepwise coordination of the imino groups to PdII in the sumanenemonoone imine compound bridged by 1,4‐benzoquinonediimine was indicated by the titration experiment. Laser irradiation of a film of the metal‐free quionediimine gave nitrogen‐doped graphitic carbon, which was supported by an increase in conductivity and by Raman spectroscopy. The obtained graphitic carbon corresponds to carbonous compounds thermally treated at approximately 700–1000 °C. The ratio of nitrogen and carbon relative to that in the starting compound was nearly completely retained (5.4 % decrease).  相似文献   
15.
The catalysis of poly(2-methoxyaniline-5-sulfonic acid) (PMAS)/gold nanoparticles catalyst was demonstrated for the dehydrogenative oxidation reaction of 2-substituted indoline and dihydropyridine under molecular oxygen in aqueous solution. This catalyst was recyclable. Redox mediating function of PMAS was revealed by following the UV-vis spectra.  相似文献   
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