Ito T  Hamaguchi Y  Tanabe K  Yamada H  Nishimoto S 《Angewandte Chemie (International ed. in English)》2012,51(30):7558-7561

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K Iwasaki  R Kanno  T Morimoto  T Yamashita  S Yokoshima  T Fukuyama 《Angewandte Chemie (International ed. in English)》2012,51(36):9160-9163

What a core-ker! The title synthesis was achieved using a route featuring an intramolecular Mitsunobu reaction of a nosyl amide, stereoselective construction of the β-lactam, and formation of an enamide moiety by selenoxide elimination. The stereochemistry of the alkylation for the formation of the β-lactam was controlled by a secondary hydroxy group on the ten-membered ring. SEM=2-(trimethylsilyl)ethoxymethyl; TBS=tert-butyldimethylsilyl.  相似文献   

    

Takeda T  Yamamoto M  Yoshida S  Tsubouchi A 《Angewandte Chemie (International ed. in English)》2012,51(29):7263-7266

Unsymmetrical ketones and allyltitanocenes generated by the desulfurizative titanation of γ,γ-disubstituted allyl phenyl sulfides react under highly diastereoselective construction of adjacent quaternary stereocenters (see scheme; R(L) = large group, R(S) = small group). The title reaction is stereospecific: the anti- and syn-homoallylic alcohols are obtained by the reaction of E- and Z-allylic sulfides, respectively.  相似文献   

    

Takeda Y  Okumura S  Minakata S 《Angewandte Chemie (International ed. in English)》2012,51(31):7804-7808

It's all the hype: An oxidative dimerization reaction of aromatic amines utilizing tert-butyl hypoiodite (tBuOI) under mild reaction conditions leads to aromatic azo compounds. The method allows access to unsymmetric aromatic azo compounds, which are difficult to prepare by conventional synthetic methods, in a selective manner.  相似文献   

    

Dr. Satoshi Ueda  Prof. Dr. Stephen L. Buchwald 《Angewandte Chemie (International ed. in English)》2012,51(41):10364-10367

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Youko Tamura  Li Sheng  Satoshi Nakazawa  Tomoya Higashihara  Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2012,50(20):4334-4340

A series of polystyrenes with phosphonic acid ( 5 ) via long alkyl side chains (4, 6, and 8 methylene units) were prepared by the radical polymerization of the corresponding diethyl ω‐(4‐vinylphenoxy)alkylphosphonates, followed by the hydrolysis with trimethylsilyl bromide. The resulting phosphonated polystyrene membranes had a high oxidative stability against Fenton's reagent at room temperature. The membranes prepared from 5 exhibited a very low water uptake, similar to that of Nafion 117 over the wide range of 30 to 80% relative humidity (RH). The proton conductivities of these membranes are lower than that of Nafion 117 in the range of 30 to 90% RH, but comparable or higher than those of the reported phosphonated polymers with higher IEC values, such as the phosphonated poly(N‐phenylacrylamide) (PDPAA, IEC: 6.72 mequiv/g) and fluorinated polymers with pendant phosphonic acids (M47, IEC: 8.5 mequiv/g), at low RH conditions despite the much lower IEC values (3.0–3.8 mequiv/g) of these membranes. These results suggest that the flexible pendant side chains of 5 would contribute to the formation of hydrogen‐bonding networks by considering the very low water uptake of these polymers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

    

Satoshi Ninomiya  Lee Chuin Chen  Hiroaki Suzuki  Yuji Sakai  Kenzo Hiraoka 《Rapid communications in mass spectrometry : RCM》2012,26(7):863-869

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Yoneho Tabata  Wataru Ito  Keichi Oshima 《高分子科学杂志，A辑:纯化学与应用化学》2013,50(4):789-799

Polymerization of tetrafluoroethylene was carried out in bulk at low temperatures by initiation with γ-rays from a ⁶⁰ Co source. It was found that a remarkable postpolymerization takes place even in the liquid phase. Kinetical analysis has been made of the in-source and postpolymerizations. An activation energy of 2.7 kcal/mole was obtained for the in-source polymerization and 10.3 kcal/mole for the postpolymerization. The long lifetime of polymer radicals in the liquid phase at -78°C seems to be due to the slow recombination rate of the polymer radicals, based on the rodlike shape of the polymer radicals.  相似文献   

    

Satoshi Iwata  Masato Senoo  Takeshi Hata  Hirokazu Urabe 《Heteroatom Chemistry》2013,24(4):336-344

N,N‐Di(arenesulfonyl)‐N′,N′‐dimethyl‐hydrazines, readily prepared from arenesulfonyl chlorides and N,N‐dimethylhydrazine, were heated at 120°C in chlorobenzene to give S‐aryl arenethiosulfonates, ArSSO₂Ar, in good yields.  相似文献   

    

Satoshi Omori  Sotaro Fuchigami  Mitsunori Ikeguchi  Akinori Kidera 《Journal of computational chemistry》2009,30(16):2602-2608

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