Shifted Selectivity in Protonation Enables the Mild Deuteration of Arenes Through Catalytic Amounts of Bronsted Acids in Deuterated Methanol
作者:Oliver Fischer、Anja Hubert、Markus R. Heinrich
DOI:10.1021/acs.joc.0c01604
日期:2020.9.18
effect” of the solvent methanol, deuterations of electron-rich aromatic systems can be carried out under mild acid catalysis and thus under far milder conditions than known so far. The exceptional functional group tolerance observed under the optimized conditions, which even includes highly acid-labile groups, results from a hitherto unexploited shifted selectivity in protonation, and enabled simple
reported. The reaction proceeds via the cleavage of a carbon–hydrogen bond at the position ortho to an alkynylgroup, and no additives are needed. Platinum complexes bearing other common ligands, such as phosphines and NHCs, failed to promote this reaction, highlighting the utility of the silylene ligand in this reaction.
Ortho-Selective Hydrogen Isotope Exchange of Phenols and Benzyl Alcohols by Mesoionic Carbene-Iridium Catalyst
作者:Liang-Liang Zhao、Yixin Wu、Shiqing Huang、Zengyu Zhang、Wei Liu、Xiaoyu Yan
DOI:10.1021/acs.orglett.1c03685
日期:2021.12.3
Hydrogenisotopeexchange reactions of phenols and benzyl alcohols have been achieved by a mesoionic carbene-iridium catalyst with high ortho selectivity and high functional group tolerance. Control experiments indicated that acetate is crucial to realize the ortho selectivity, whereas density functional theory calculations supported an outer-sphere direction with hydrogen bonding between acetate and
FeCl<sub>3</sub>-Mediated Friedel-Crafts Hydroarylation with Electrophilic<i>N</i>-Acetyl Indoles for the Synthesis of Benzofuroindolines
作者:Rodolphe Beaud、Régis Guillot、Cyrille Kouklovsky、Guillaume Vincent
DOI:10.1002/anie.201206611
日期:2012.12.7
IRONic electrophilicindoles! The C3‐regioselectivehydroarylation of N‐acetyl indoles with aromatic nucleophiles mediated by FeCl3 features a rare example of the electrophilic reactivity of the indole core in a Friedel–Crafts reaction. This indole umpolung allows us straightforward access to the tetracyclic benzofuroindoline motif found in the natural product diazonamide A, which is a potent antitumor