Photoenzymatic Hydrogenation of Heteroaromatic Olefins Using ‘Ene’‐Reductases with Photoredox Catalysts
作者:Yuji Nakano、Michael J. Black、Andrew J. Meichan、Braddock A. Sandoval、Megan M. Chung、Kyle F. Biegasiewicz、Tianyu Zhu、Todd K. Hyster
DOI:10.1002/anie.202003125
日期:2020.6.22
selective catalysts for the asymmetric reduction of activated alkenes. This function is, however, limited to enones, enoates, and nitroalkenes using the native hydride transfer mechanism. Here we demonstrate that EREDs can reduce vinyl pyridines when irradiated with visible light in the presence of a photoredoxcatalyst. Experimental evidence suggests the reaction proceeds via a radical mechanism where
Catalytic α-Deracemization of Ketones Enabled by Photoredox Deprotonation and Enantioselective Protonation
作者:Chenhao Zhang、Anthony Z. Gao、Xin Nie、Chen-Xi Ye、Sergei I. Ivlev、Shuming Chen、Eric Meggers
DOI:10.1021/jacs.1c06637
日期:2021.8.25
deprotonation, followed by enantioselective protonation. The principle of microscopic reversibility, which has previously rendered this strategy elusive, is overcome by a photoredox deprotonation through single electron transfer and subsequent hydrogen atom transfer (HAT). Specifically, the irradiation of racemic pyridylketones in the presence of a single photocatalyst and a tertiary amine provides nonracemic
sp<sup>3</sup>C–H bond alkylation of ketones with alkenes via ruthenium(<scp>ii</scp>) catalysed dehydrogenation of alcohols
作者:Bin Li、Christophe Darcel、Pierre H. Dixneuf
DOI:10.1039/c4cc00931b
日期:——
The sp(3)C-H bond functionalisation of 2-pyridyl ethanols upon reaction with alkenes, in the presence of a [RuCl2(arene)]2 catalyst and Cu(OAc)2.H2O, is performed under mild conditions without additional base. This reaction proceeds via a tandem alcohol dehydrogenation/alkylation with alkenes of the resulting ketone at its alpha sp(3)C-H bond.
Diverse Alkanones by Catalytic Carbon Insertion into the Formyl C−H Bond. Concise Access to the Natural Precursor of Achyrofuran
作者:Andrew J. Wommack、David C. Moebius、Austin L. Travis、Jason S. Kingsbury
DOI:10.1021/ol9010932
日期:2009.8.6
Over a century ago, the first reactions of diazomethane with aldehydes delivered methyl ketones. In the interim, aldehydes have been homologated with trimethylsilyldiazomethane, diazoacetates, and aryldiazomethanes, on rare occasion with catalysis. This work describes a mild procedure for convergent ketone assembly from nonstabilized diazoalkanes, including examples of chiral ketone synthesis with
The first Pd-catalyzed alkylation of (iso)quinolines and arenes is reported. The readily available and bench-stable 2-acylpyridine compounds were used as an alkylation reagent to form the structurally versatile alkylated (iso)quinolines and arenes. The method affords a convenient pathway for the introduction of alkyl groups into organic molecules.