Photocatalytic esterification under Mitsunobu reaction conditions mediated by flavin and visible light
作者:M. März、J. Chudoba、M. Kohout、R. Cibulka
DOI:10.1039/c6ob02770a
日期:——
The usefulness of flavin-based aerial photooxidation in esterification underMitsunobu reaction conditions was demonstrated, providing aerial dialkyl azodicarboxylate recycling/generation from the corresponding dialkyl hydrazine dicarboxylate. Simultaneously, activation of triphenylphosphine (Ph3P) by photoinduced electron transfer from flavin allows azo-reagent-free esterification. An optimized system
Flavin Catalysis Employing an N(5)-Adduct: an Application in the Aerobic Organocatalytic Mitsunobu Reaction
作者:Michal März、Martin Babor、Radek Cibulka
DOI:10.1002/ejoc.201900397
日期:2019.6.2
An N(5)‐flavin adduct was utilized in a catalytic Mitsunobureaction with triphenylphosphane (triphenylphosphine), in which flavin acts as a Mitsunobu reagent instead of dialkyl azodicarboxylate. Flavin is used in a catalytic amount after regeneration by dioxygen.
single-electron oxidation. Unexpected stereoselectivity control by the solvent was observed, allowing switching from inversion to retention of configuration during esterification of (S)- or (R)-1-phenylethanol; for example with phenylacetic acid, the ratio shifting from 10 : 90 (retention : inversion) in trifluoromethylbenzene to 99.9 : 0.1 in acetonitrile. Our method uses nitrobenzene to regenerate the flavin
Scandium triflate catalyzed ester synthesis using primary amides
作者:Benjamin N. Atkinson、Jonathan M.J. Williams
DOI:10.1016/j.tetlet.2014.10.124
日期:2014.12
A scandium triflate (ScOTf)(3) catalyzed methodology has been developed to synthesize esters from primary amides. Various primary and secondary aliphatic alcohols have been shown to react in n-heptane with a range of primary amides for 24 h. (C) 2014 The Authors. Published by Elsevier Ltd.
Highly Selective Hydrogenation of C═C Bonds Catalyzed by a Rhodium Hydride
作者:Yiting Gu、Jack R. Norton、Farbod Salahi、Vladislav G. Lisnyak、Zhiyao Zhou、Scott A. Snyder
DOI:10.1021/jacs.1c04683
日期:2021.6.30
Undermildconditions (room temperature, 80 psi of H2) Cp*Rh(2-(2-pyridyl)phenyl)H catalyzes the selectivehydrogenation of the C═C bond in α,β-unsaturated carbonyl compounds, including natural product precursors with bulky substituents in the β position and substrates possessing an array of additional functionalgroups. It also catalyzes the hydrogenation of many isolated double bonds. Mechanistic
在温和条件下(室温,80 psi H 2)Cp*Rh(2-(2-吡啶基)苯基)H催化α,β-不饱和羰基化合物(包括天然产物前体)中C=C键的选择性氢化在 β 位具有庞大的取代基,并且底物具有一系列额外的官能团。它还催化许多分离的双键的氢化。机理研究表明,不涉及自由基中间体,并且催化剂似乎是均相的,从而为类似氢化过程的现有方案提供了重要的互补性。