Modular Functionalization of Arenes in a Triply Selective Sequence: Rapid C(sp<sup>2</sup>
) and C(sp<sup>3</sup>
) Coupling of C−Br, C−OTf, and C−Cl Bonds Enabled by a Single Palladium(I) Dimer
作者:Sinead T. Keaveney、Gourab Kundu、Franziska Schoenebeck
DOI:10.1002/anie.201808386
日期:2018.9.17
competing coupling sites would enable straightforward access to densely functionalized compound libraries. Historically, the site selection in Pd0‐catalyzed functionalizations of poly(pseudo)halogenated arenes has been unpredictable, being dependent on the employed catalyst, the reaction conditions, and the substrate itself. Building on our previous report of C−Br‐selectivefunctionalization in the presence
Regioselective Nucleophilic Addition of Organometallic Reagents to 3-Geminal Bis(silyl) <i>N</i>-Acyl Pyridinium
作者:Ya Wu、Linjie Li、Hongze Li、Lu Gao、Hengmu Xie、Zhigao Zhang、Zhishan Su、Changwei Hu、Zhenlei Song
DOI:10.1021/ol500302r
日期:2014.4.4
bis(silyl) N-acyl pyridinium has been described. Geminal bis(silane) shows contrasting roles that lead to different regioselectivities for the addition of different nucleophiles: its steric effect dominates to favor 1,6-addition of alkyl, vinyl, and aryl organometallicreagents; its directing effect dominates to favor 1,2-addition of less sterically demanding alkynyl Grignard reagents.
A general, versatile method for alkylation and arylation of haloheterocyclic compounds is reported. In the presence of a catalytic quantity of [NiCl2(dppp)], where dppp stands for Ph2P(CH2)3PPh2, bromothiophenes, halopyridines, haloquinoline, and haloisoquinolines reacted with alkyl and aryl Grignard reagents at room temperature or at ether refluxing temperature to give the cross-coupling products
Tandem Mn–I Exchange and Homocoupling Processes Mediated by a Synergistically Operative Lithium Manganate
作者:Marina Uzelac、Pasquale Mastropierro、Marco Tullio、Ivana Borilovic、Màrius Tarrés、Alan R. Kennedy、Guillem Aromí、Eva Hevia
DOI:10.1002/anie.202013153
日期:2021.2.8
Pairing lithium and manganese(II) to form lithiummanganate [Li2Mn(CH2SiMe3)4] enables the efficient direct Mn–Iexchange of aryliodides, affording transient (aryl)lithiummanganate intermediates which in turn undergo spontaneous C−C homocoupling at room temperature to furnish symmetrical (bis)aryls in good yields under mild reaction conditions. The combination of EPR with X‐ray crystallographic studies