α,α-Alkylation-Halogenation and Dihalogenation of Sulfoxonium Ylides. A Direct Preparation of Geminal Difunctionalized Ketones
作者:Rafael D. C. Gallo、Anees Ahmad、Gustavo Metzker、Antonio C. B. Burtoloso
DOI:10.1002/chem.201704609
日期:2017.12.1
A one‐pot alkylation–halogenation of ketosulfoxonium ylides in the presence of alkyl halides is described. The method furnishes several gem‐difunctionalized haloketones (an alkyl and F, Cl, Br, or I) in good yields. Replacing alkyl halides with a mixture of electrophilic halogen species and various halide anions led to gem‐dihalogenated ketones containing a combination of the same or two different
Ring-Opening Diarylation of Siloxydifluorocyclopropanes by Ag(I) Catalysis: Stereoselective Construction of 2-Fluoroallylic Scaffold
作者:Xiaoning Song、Cong Xu、Dongxu Du、Ziming Zhao、Dongsheng Zhu、Mang Wang
DOI:10.1021/acs.orglett.7b03254
日期:2017.12.15
A silver-catalyzed, defluorination ring-opening diarylation of siloxy 2,2-difluorocyclopropanes, with two arenes, to directly prepare polysubstituted 2-fluoroallylic compounds, is described. This multicomponent reaction proceeds smoothly in good stereoselectivity, which is due to a chelation-controlled addition of arenes to α-fluorinated ketone intermediate.
Brønsted Base-Catalyzed Transformation of α,β-Epoxyketones Utilizing [1,2]-Phospha-Brook Rearrangement for the Synthesis of Allylic Alcohols Having a Tetrasubstituted Alkene Moiety
stereoselective transformation of α,β-epoxyketones into alkenylphosphates having a hydroxymethyl group on the β-carbon was established by utilizing the [1,2]-phospha-Brook rearrangement under Brønsted base catalysis. The reaction involves the catalytic generation of an α-oxygenated carbanion located at the α-position of an epoxide moiety through the [1,2]-phospha-Brook rearrangement and the following
An expedient synthesis of poly-substituted pyrroles from γ-ketonitriles via indium-mediated Barbier reaction strategy
作者:Sung Hwan Kim、Se Hee Kim、Ka Young Lee、Jae Nyoung Kim
DOI:10.1016/j.tetlet.2009.07.140
日期:2009.10
We developed an efficient synthetic strategy of poly-substituted pyrroles via an indium-mediated Barbier type allylation from gamma-ketonitriles. Initial attack of allylindium species occurred at the nitrile group selectively to form the enamine intermediate, which reacted with the ketone group intramolecularly to furnish the pyrroles. (C) 2009 Elsevier Ltd. All rights reserved.
Electro‐mediated PhotoRedox Catalysis for Selective C(sp
<sup>3</sup>
)–O Cleavages of Phosphinated Alcohols to Carbanions
作者:Xianhai Tian、Tobias A. Karl、Sebastian Reiter、Shahboz Yakubov、Regina Vivie‐Riedle、Burkhard König、Joshua P. Barham
DOI:10.1002/anie.202105895
日期:2021.9.13
As well as deoxygenations, olefinations are reported which are E-selective and can be made Z-selective in a tandem reduction/photosensitization process where both steps are photoelectrochemically promoted. Spectroscopy, computation, and catalyst structural variations reveal that our new naphthalene monoimide-type catalyst allows for an intimate dispersive precomplexation of its radical anion form with