Search Results - "TOKUYASU, Takahiro"

Electrophilicities of Benzaldehyde-Derived Iminium Ions: Quantification of the Electrophilic Activation of Aldehydes by Iminium Formation by Appel, Roland, Chelli, Saloua, Tokuyasu, Takahiro, Troshin, Konstantin, Mayr, Herbert

“…Rate constants for the reactions of benzaldehyde-derived iminium ions with C-nucleophiles (enamines, silylated ketene acetals, and enol ethers) have been…”
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Nucleophilic Reactivities of Ketene Acetals by Tokuyasu, Takahiro, Mayr, Herbert

“…The kinetics of the reactions of ketene acetals with benzhydrylium ions have been followed photometrically. The reactions proceed with rate‐determining C−C…”
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Nucleophilic Reactivities of Imide and Amide Anions by Breugst, Martin, Tokuyasu, Takahiro, Mayr, Herbert

“…The kinetics of the reactions of amide and imide anions 2a−o with benzhydrylium ions 1a−i and structurally related quinone methides 1j−q have been studied by…”
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Electrophilic Reactivities of α,β-Unsaturated Iminium Ions by Lakhdar, Sami, Tokuyasu, Takahiro, Mayr, Herbert

“…How fast do nucleophiles add to iminium ions? Kinetic studies of the reactions of seven iminium ions 1 with cyclic ketene acetals 2 rendered electrophilicity…”
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The synthesis and crystal structure analysis of novel macrocyclic peroxides by McCullough, Kevin J, Ito, Toyonari, Tokuyasu, Takahiro, Masuyama, Araki, Nojima, Masatomo

“…Bis( syn-collidine)iodine(I) hexafluorophosphate-mediated cyclization of unsaturated hydroperoxides afforded the corresponding 11- to 16-membered macrocyclic…”
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Solvation Accounts for the Counterintuitive Nucleophilicity Ordering of Peroxide Anions by Mayer, Robert J., Tokuyasu, Takahiro, Mayer, Peter, Gomar, Jérôme, Sabelle, Stéphane, Mennucci, Benedetta, Mayr, Herbert, Ofial, Armin R.

“…The nucleophilic reactivities (N, sN) of peroxide anions (generated from aromatic and aliphatic peroxy acids or alkyl hydroperoxides) were investigated by…”
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Co(III)−Alkyl Complex- and Co(III)−Alkylperoxo Complex-Catalyzed Triethylsilylperoxidation of Alkenes with Molecular Oxygen and Triethylsilane by Tokuyasu, Takahiro, Kunikawa, Shigeki, Masuyama, Araki, Nojima, Masatomo

“…Both a Co(III)−alkyl complex and a Co(III)−alkylperoxo complex were found to catalyze triethylsilylperoxidation of alkenes with O2 and Et3SiH. On this basis,…”
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Synthesis of Cyclic Peroxides by Chemo- and Regioselective Peroxidation of Dienes with Co(II)/O2/Et3SiH by Tokuyasu, Takahiro, Kunikawa, Shigeki, McCullough, Kevin J, Masuyama, Araki, Nojima, Masatomo

“…In the competitive peroxidation of mixtures of two alkenes with Co(II)/O2/Et3SiH, it was found that the relative reactivities of the alkene substrates are…”
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Synthesis of 3-Hydroperoxy (or Hydroxy)-substituted 1,2-Dioxanes and 1,2-Dioxepanes by the Ozonolysis of Unsaturated Hydroperoxy Acetals by Nojima, Masatomo, Tokuyasu, Takahiro, Ito, Toyonari, Masuyama, Araki

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Synthesis of novel macrocyclic peroxides by bis(sym-collidine)iodine (I) hexafluorophosphate-mediated cyclization of unsaturated hydroperoxides and unsaturated alcohols by Ito, Toyonari, Tokuyasu, Takahiro, Masuyama, Araki, Nojima, Masatomo, McCullough, Kevin J

“…Bis(sym-collidine)iodine (I) hexafluorophosphate-mediated cyclization of unsaturated hydroperoxides, prepared by a variety of different methods, afforded the…”
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Synthesis of Antimalarial Yingzhaosu A Analogues by the Peroxidation of Dienes with Co(II)/O2/Et3SiH by Tokuyasu, Takahiro, Kunikawa, Shigeki, Abe, Manabu, Masuyama, Araki, Nojima, Masatomo, Kim, Hye-Sook, Begum, Khurshida, Wataya, Yusuke

“…Co(II)-catalyzed peroxidation of dienes including (S)-limonene in the presence of molecular oxygen and triethylsilane provided in each case the corresponding…”
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Elektrophile Reaktivität α,β‐ungesättigter Iminiumionen by Lakhdar, Sami, Tokuyasu, Takahiro, Mayr, Herbert

“…Wie rasch reagieren Iminiumionen mit Nucleophilen? Messungen der Reaktionskinetik für die Umsetzung von sieben Iminiumionen 1 mit cyclischen Ketenacetalen 2…”
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Solvatation als Ursache für die unerwartete Nucleophilie‐Reihung von Peroxid‐Anionen by Mayer, Robert J., Tokuyasu, Takahiro, Mayer, Peter, Gomar, Jérôme, Sabelle, Stéphane, Mennucci, Benedetta, Mayr, Herbert, Ofial, Armin R.

“…Die nucleophilen Reaktivitäten (N, sN) von Peroxid‐Anionen (aus aromatischen und aliphatischen Persäuren oder Alkylhydroperoxiden generiert) wurden durch…”
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Co-catalyzed autoxidation of alkene in the presence of silane. The effect of the structure of silanes on the efficiency of the reaction and on the product distribution by Wu, Jin-Ming, Kunikawa, Shigeki, Tokuyasu, Takahiro, Masuyama, Araki, Nojima, Masatomo, Kim, Hye-Sook, Wataya, Yusuke

“…A systematic investigation of the structural effect of silanes on the Co-catalyzed reductive oxygenation of alkene in the presence of silane (Mukaiyama–Isayama…”
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Solvatation als Ursache für die unerwartete Nucleophilie‐Reihung von Peroxid‐Anionen by Mayer, Robert J., Tokuyasu, Takahiro, Mayer, Peter, Gomar, Jérôme, Sabelle, Stéphane, Mennucci, Benedetta, Mayr, Herbert, Ofial, Armin R.

“…Abstract Die nucleophilen Reaktivitäten ( N , s N ) von Peroxid‐Anionen (aus aromatischen und aliphatischen Persäuren oder Alkylhydroperoxiden generiert)…”
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Synthesis of cyclic peroxides by chemo- and regioselective peroxidation of dienes with Co(II)/O2Et3SiH by TOKUYASU, Takahiro, KUNIKAWA, Shigeki, MCCULLOUGH, Kevin J, MASUYAMA, Araki, NOJIMA, Masatomo

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Synthesis of Cyclic Peroxides by Chemo- and Regioselective Peroxidation of Dienes with Co(II)/O 2 /Et 3 SiH by Tokuyasu, Takahiro, Kunikawa, Shigeki, McCullough, Kevin J., Masuyama, Araki, Nojima, Masatomo

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Yingzhaosu A analogues: synthesis by the ozonolysis of unsaturated hydroperoxides, structural analysis and determination of anti-malarial activity by Tokuyasu, Takahiro, Masuyama, Araki, Nojima, Masatomo, McCullough, Kevin J, Kim, Hye-Sook, Wataya, Yusuke

“…Ozone-mediated cyclization of a series of unsaturated hydroperoxides 7, prepared from dienes 2, afforded the corresponding yingzhaosu A analogues 9 in moderate…”
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Halonium Ion-Mediated Reaction of Unsaturated Hydroperoxy Acetals. Competition between the Formation of Cyclic Peroxides and the Migration of the Methoxy (or Hydroxy) Group by Tokuyasu, Takahiro, Masuyama, Araki, Nojima, Masatomo, McCullough, Kevin J

“…Monoozonolyses of dienes 2 in methanol gave in each case the corresponding unsaturated α-methoxy hydroperoxides 3. Capture of 2-alkyl-substituted cyclohexanone…”
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Synthesis of Antimalarial Yingzhaosu A Analogues by the Peroxidation of Dienes with Co(II)/O 2 /Et 3 SiH by Tokuyasu, Takahiro, Kunikawa, Shigeki, Abe, Manabu, Masuyama, Araki, Nojima, Masatomo, Kim, Hye-Sook, Begum, Khurshida, Wataya, Yusuke

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