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371.
Hiroto Kudo Tadatomi Nishikubo 《Journal of polymer science. Part A, Polymer chemistry》2007,45(5):709-726
This paper reports new addition reactions of oxetanes with certain protonic reagents such as carboxylic acid, phenol, and thiol, and with certain aprotic reagents such as acyl chloride, thioester, phosphonyl dichloride, silyl chloride, and chloroformate using quaternary onium salts as catalysts. The kinetic study of the addition reactions of oxetanes was also investigated. These new addition reactions were applicable to the synthesis of new polymers. These polyaddition systems could also construct both polymer main chains and reactive side chains. The alternating copolymerization of oxetanes with carboxylic anhydride was performed. Furthermore, it was found that anionic ring‐opening polymerization of oxetanes containing hydroxy groups proceeded to afford the hyperbranched polymer (HBP) with an oxetanyl group and many hydroxy groups at the ends of the polymer chains. Alkali developable photofunctional HBPs were synthesized by the polyaddition of bis(oxetane)s or tris(oxetane)s, and their patterning properties were examined, too. The photo‐induced cationic polymerization of the polymers with pendant oxetanyl groups and the thermal curing reactions of polyfunctional oxetanes (oxetane resins) were also examined to give the crosslinking materials quantitatively. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 709–726, 2007 相似文献
372.
Satoru Hiroto Naoki Aratani Dr. Naoki Shibata Prof. Dr. Yoshiki Higuchi Prof. Dr. Takahiro Sasamori Dr. Norihiro Tokitoh Prof. Dr. Hiroshi Shinokubo Prof. Dr. Atsuhiro Osuka Prof. Dr. 《Angewandte Chemie (International ed. in English)》2009,48(13):2388-2390
Pyridine attacks : Nucleophilic addition of pyridine derivatives to a doubly linked corrole, which is a stable singlet biradical species, occurs at the bay area with high regioselectivity to provide zwitterionic dimers (see picture; Ar=C6F5). Charge transfer between the anionic corrole and the pyridinium groups induces effective fluorescence quenching of the corrole dimer, which can be utilized for selective fluoride ion recognition.
373.
Hiroto Watanabe 《Tetrahedron letters》2005,46(40):6815-6818
Diels-Alder reactions in a solid state between anthracene (AN) derivatives and p-benzoquinone (BQ) under mechanical stressing are accelerated by adding a catalytic amount of 2-naphthol (NP) or (rac)-1,1′-bis-2-naphthol (BN). Their catalytic effects are based on the formation of the charge transfer complex with strong hydrogen bonds. BN is capable of incorporating BQ together with its reaction partner, AN derivatives, simultaneously. The resulted molecular complex with BN provides crystallographically ordered homogenic reaction fields, resulting in the higher rates of the present solid state Diels-Alder reaction. 相似文献
374.
[reaction: see text] A novel synthetic approach to N-alkyl-N'-arylimidazolium salts has been developed on the basis of addition of imidazoles to arynes. A variety of N-alkyl-N'-arylimidazolium salts can be synthesized straightforwardly in modest to good yields. Furthermore, utility of the resulting imidazolium salts has been demonstrated by the palladium-catalyzed Suzuki-Miyaura coupling of aryl chlorides. 相似文献
375.
We synthesized cyclic tetrathioesters containing thioester moieties at the o‐position (o‐CTE) and m‐position (m‐CTE) of an aromatic skeleton. The reaction of phenoxy propylenesulfide (PPS) with o‐CTE and m‐CTE was examined using tetrabutylammonium chloride as a catalyst in 1‐methyl‐2‐pyrrolidinone, yielding the corresponding cyclic polysulfides poly[o‐CTE(PPS)n] with Mn's = 37,000–54,000 at 34–61% yields and poly[m‐CTE(PPS)n] with Mn's = 46,600–107,200 at 63–>99% yields. Although the molecular weights of poly[o‐CTE(PPS)n] could not be controlled, those of poly[m‐CTE(PPS)n] could be controlled by the feed ratios of PPS and reaction temperature. Furthermore, the glass transition temperature (Tg) and thermal decomposition temperature (Tdi) of poly[m‐CTE(PPS)n] increased with decreasing molecular weights. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 857–866 相似文献
376.
Desmopyridine, isolated from the acid hydrolysates of bovine ligamentum nuchae, is an elastin crosslinker and an amino acid that has a 3,4,5-trisubstituted pyridine skeleton. Herein we report the first total synthesis of (+)-desmopyridine in 10% yield over six steps starting from 4-aminopyridine via chemo- and regioselective palladium-catalyzed Sonogashira and Negishi cross-coupling reactions. 相似文献
377.
Hiroto Kudo Toshiki Ohshiro Hiroyuki Atsumi Ayako Kamio Tadatomi Nishikubo Saeko Murakami 《Journal of polymer science. Part A, Polymer chemistry》2012,50(3):458-465
A new synthetic strategy for polymers containing amino acids in the main chain was developed. Monomers N‐oxetanylalanine (N‐Oxe‐Ala‐COOH), N‐oxetanylglutamic acid (N‐Oxe‐Glu‐COOH), and N‐oxetanyllysine (N‐Oxe‐Lys‐COOH) containing both oxetanyl and carboxyl groups were synthesized, and self‐polyaddition and self‐copolyaddition of these monomers afforded the corresponding polymers containing amino acids in the main chain [poly(OxAla), poly(OxLys), poly(OxGlu), poly(OxAla‐co‐OxGlu), poly(OxGlu‐co‐OxLys), and poly(OxAla‐co‐OxLys)] with molecular weight in the range of 920–6620, in satisfactory yields. The physical properties, such as solubility, glass transition temperature, and thermal stability, were consistent with the amount of carboxyl groups at the chain ends. Biodegradability of the polymers was examined by the biochemical oxygen demand method; the decomposition ratios of poly(OxAla) and poly(OxAla‐co‐OxGlu) were about 60%, whereas that of poly(OxGlu) was nearly 100% after 28 days. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
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