Copper(I)-Catalyzed Coupling of Terminal Acetylenes with Aryl or Vinyl Halides
作者:D. Venkataraman、Pranorm Saejueng、Craig G. Bates
DOI:10.1055/s-2005-869893
日期:——
Synthetic protocols using copper(I) catalysts for the for- mation of diaryl acetylenes, 1,3-enynes, benzofurans and indoles are described. The acetylenic moiety is an important unit found in many compounds that are of pharmaceutical, biological and ma- terial interests. 1 Aryl acetylenes are constituent units in important conjugated polymers. 1c 1,3-Enynes are found in many biologically and pharmaceutically
Enantioselective Synthesis of α-Chiral Propargylic Silanes by Copper-Catalyzed 1,4-Selective Addition of Silicon Nucleophiles to Enyne-Type α,β,γ,δ-Unsaturated Acceptors
作者:Wenbin Mao、Martin Oestreich
DOI:10.1021/acs.orglett.0c03046
日期:2020.10.16
A copper-catalyzed deconjugative addition of silicon nucleophiles to a broad range of enyne-type α,β,γ,δ-unsaturated acceptors with high enantiocontrol is reported. The method is 1,4-selective with hardly any formation of the 1,6-adduct. The double-bond geometry is shown to be critical for achieving this chemoselectivity: exclusive 1,4-addition for E and predominant 1,6-addition for Z. By this, E-configured
The Pd(II)-catalyzed one-pot tandem cyclization/alkylation reactions of enynoates with allylic alcohols have been demonstrated. In this reaction, an innovative protocol proceeded well through Pd-catalyzed intramolecular selective 6-endo cyclization, insertion of allylic alcohols into the Pd–C bond of vinylpalladium species generated in situ, and β-hydrogen elimination processes. This conversion provides
In Situ Formation of RSCl/ArSeCl and Their Application to the Synthesis of 4-Chalcogenylisocumarins/Pyrones from <i>o</i>-(1-Alkynyl)benzoates and (<i>Z</i>)-2-Alken-4-ynoates
作者:Linlin Xing、Yong Zhang、Bing Li、Yunfei Du
DOI:10.1021/acs.orglett.9b01046
日期:2019.5.17
diorganyl disulfides or diselenides with PhICl2 in acetonitrile was found for the first time to lead to the in situ formation of organosulfenyl chloride or selenenyl chloride, which enables the regioselective intramolecular chalcogenylacyloxylation of alkynes resulting in the formation of 4-chalcogenylisocumarins/pyrones in good to excellent yields under metal-free conditions.
Stoichiometric and Catalytic C−C and C−H Bond Formation with B(C<sub>6</sub>
F<sub>5</sub>
)<sub>3</sub>
via Cationic Intermediates
作者:Yashar Soltani、Lewis C. Wilkins、Rebecca L. Melen
DOI:10.1002/anie.201704789
日期:2017.9.18
concomitant C−H or C−C bondformation. The activation of alkyne‐containing substrates with B(C6F5)3 enabled the first catalytic intramolecular cyclizations of carboxylic acid substrates using this Lewis acid. In addition, intramolecular cyclizations of esters enable C−C bondformation as catalytic B(C6F5)3 can be used to effect formal 1,5‐alkyl migrations from the ester functional groups to unsaturated carbon–carbon
这项工作展示了一种新的催化环化反应,该反应使用高度路易斯酸的硼烷并伴有CH或CC键的形成。用B(C 6 F 5)3活化含炔的底物使得能够使用该路易斯酸对羧酸底物进行第一个催化的分子内环化反应。此外,酯的分子内环化使CC键形成为催化性B(C 6 F 5)3。可用于实现从酯官能团到不饱和碳-碳骨架的正式1,5-烷基迁移。该无金属方法用于在相对温和的条件下以极高的收率和极好的原子效率催化形成复杂的二氢吡喃酮和异香豆素。