K<sub>2</sub>S<sub>2</sub>O<sub>8</sub>-Mediated Selective Trifluoromethylacylation and Trifluoromethylarylation of Alkenes under Transition-Metal-Free Conditions: Synthetic Scope and Mechanistic Studies
on and -arylation of alkenes with inexpensive CF3SO2Na and K2S2O8 in aqueous media has been developed, respectively, affording the highly chemoselective synthesis of CF3-functionalized chroman-4-ones and chromanes in satisfactory yields. Control experiments and DFT calculations indicate that the CF3SO2Na/K2S2O8 system is capable of trifluoromethylating the substrate of alkenes without a transition
作者:Chetan C. Chintawar、Amit K. Yadav、Nitin T. Patil
DOI:10.1002/anie.202002141
日期:2020.7.13
Herein, we disclose the gold‐catalyzed 1,2‐diarylation of alkenes through the interplay of ligand‐enabled AuI/AuIII catalysis with the idiosyncratic π‐activation mode of gold complexes. Unlike the classical migratory‐insertion‐based approach to 1,2‐diarylation, the present approach not only circumvents the formation of direct Ar−Ar′ coupling and Heck‐type side products but more intriguingly demonstrates
本文中,我们通过配体使能的Au I / Au III催化与金配合物的特质π活化模式的相互作用揭示了金的烯烃1,2-二芳基化反应。与经典的基于迁移插入的方法进行1,2-二芳基化不同,本方法不仅规避了直接Ar-Ar'偶联和Heck型副产物的形成,而且更有趣地证明了其反应性和选择性与先前已知的互补金属催化(Pd,Ni或Cu)。对机理进行详细研究的结果表明,由于芳基烯烃具有非清白的性质,芳基碘化物向Au I络合物的氧化加成是限速步骤。
A new shelf‐stable and easily scalable difluoromethylthiolating reagent S‐(difluoromethyl) benzenesulfonothioate (PhSO2SCF2H) was developed. PhSO2SCF2H is a powerful reagent for radical difluoromethylthiolation of aryl and alkyl boronic acids, decarboxylative difluoromethylthiolation of aliphatic acids, and a phenylsulfonyl‐difluoromethylthio difunctionalization of alkenes under mild reaction conditions
A simple and practical photochemical strategy for intermolecular perfluoroalkyl-alkenylation of alkenes with 2-amino-1,4-naphthoquinones and perfluoroalkyl iodides has been demonstrated under visible-light irradiation. Mechanistic studies reveal that easily available 2-amino-1,4-naphthoquinone substrates can serve as efficient photosensitizers to activate perfluoroalkyl iodides through a photoredox