1007-48-3Relevant articles and documents
Catalytic acyl transfer by a cyclic porphyrin trimer: Efficient turnover without product inhibition
Mackay, Lindsey G.,Wylie, R. Stephen,Sanders, Jeremy K. M.
, p. 3141 - 3142 (1994)
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Spin-Center Shift-Enabled Direct Enantioselective α-Benzylation of Aldehydes with Alcohols
Nacsa, Eric D.,MacMillan, David W. C.
, p. 3322 - 3330 (2018)
Nature routinely engages alcohols as leaving groups, as DNA biosynthesis relies on the removal of water from ribonucleoside diphosphates by a radical-mediated "spin-center shift" (SCS) mechanism. Alcohols, however, remain underused as alkylating agents in synthetic chemistry due to their low reactivity in two-electron pathways. We report herein an enantioselective α-benzylation of aldehydes using alcohols as alkylating agents based on the mechanistic principle of spin-center shift. This strategy harnesses the dual activation modes of photoredox and organocatalysis, engaging the alcohol by SCS and capturing the resulting benzylic radical with a catalytically generated enamine. Mechanistic studies provide evidence for SCS as a key elementary step, identify the origins of competing reactions, and enable improvements in chemoselectivity by rational photocatalyst design.
Signal amplification and detection via a supramolecular allosteric catalyst
Gianneschi, Nathan C.,Nguyen, SonBinh T.,Mirkin, Chad A.
, p. 1644 - 1645 (2005)
The design of a supramolecular allosteric catalyst system for catalytic signal amplification and detection is presented. The catalyst was switched on by the introduction of an analyte that also behaves as an allosteric activator. Concentrations of Cl- ions as low as 800 nM were catalytically amplified and detected. The signal was transduced via a pH-sensitive fluorescent probe and observed visually using a laboratory, handheld UV lamp and by spectrophotometry. Furthermore, the allosteric effect was quantified using gas chromatography for a range of Cl- concentrations. This three-part detection scheme involving analyte binding, allosteric catalyst activation, and signal transduction represents a new approach to small-molecule detection. Copyright
Proton-exchanged montmorillonite-mediated reactions of hetero-benzyl acetates: Application to the synthesis of Zafirlukast
Yang, Lei,Chen, Xuan,Ni, Kaidong,Li, Yuansheng,Wu, Jianhong,Chen, Weilin,Ji, Yin,Feng, Lili,Li, Fei,Chen, Dongyin
supporting information, (2020/06/28)
Proton-exchanged montmorillonite (H-mont) with outstanding surface characteristics can provide abundant acidic sites in the mesopores, and serve as an efficient heterogeneous catalyst for the synthesis of heterocycle-containing diarylmethanes via Friedel-Crafts-like alkylation of (hetero)arenes by heterobenzyl acetates under mild reaction conditions without requiring any additives or an inert atmosphere. Using this strategy, the gram-scale synthesis of indole-containing diarylmethane 13 has been accomplished in good yield for the preparation of Zafirlukast. In addition, H-mont can be applied to the nucleophilic substitution reactions of heterobenzyl acetate 5p with a variety of alcohols and 1,3-dicarbonyl compounds.
