Iron-Catalyzed Difluoromethylation of Arylzincs with Difluoromethyl 2-Pyridyl Sulfone
作者:Wenjun Miao、Yanchuan Zhao、Chuanfa Ni、Bing Gao、Wei Zhang、Jinbo Hu
DOI:10.1021/jacs.7b11976
日期:2018.1.24
We report the first iron-catalyzed difluoromethylation of arylzincs with difluoromethyl2-pyridylsulfone via selective C-S bond cleavage. This method employs the readily available, bench-stable fluoroalkyl sulfone reagent and inexpensive iron catalyst, allowing facile access to structurally diverse difluoromethylated arenes at low temperatures. The experiment employing a radical clock indicates the
Decarboxylative Negishi Coupling of Redox‐Active Aliphatic Esters by Cobalt Catalysis
作者:Xu‐Ge Liu、Chu‐Jun Zhou、E. Lin、Xiang‐Lei Han、Shang‐Shi Zhang、Qingjiang Li、Honggen Wang
DOI:10.1002/anie.201806799
日期:2018.10
A cobalt‐catalyzed decarboxylative Negishi coupling reaction of redox‐active aliphatic esters with organozinc reagents was developed. The method enabled efficient alkyl–aryl, alkyl–alkenyl, and alkyl–alkynyl coupling reactions under mild reaction conditions with no external ligand or additive needed. The success of an in situ activation protocol and the facile synthesis of the drug molecule (±)‐preclamol
Three‐Component Difunctionalization of Cyclohexenyl Triflates: Direct Access to Versatile Cyclohexenes via Cyclohexynes
作者:Seoyoung Cho、E. J. McLaren、Qiu Wang
DOI:10.1002/anie.202109482
日期:2021.12.6
dicarbofunctionalization, aminohalogenation and aminocarbonation of readily available cyclohexenyl triflates, via strained cyclic alkyne intermediates generated in situ. The importance and utility of this method is exemplified by the modularity of this approach and the ease in which even highly complex polycyclic scaffolds can be accessed in one step.
Quaternary Centers by Nickel‐Catalyzed Cross‐Coupling of Tertiary Carboxylic Acids and (Hetero)Aryl Zinc Reagents
作者:Tie‐Gen Chen、Haolin Zhang、Pavel K. Mykhailiuk、Rohan R. Merchant、Courtney A. Smith、Tian Qin、Phil S. Baran
DOI:10.1002/anie.201814524
日期:2019.2.18
redox-active esters with aryl zinc reagents. Previously limited to primary, secondary, and specialized tertiary centers, a new protocol has been devised to enable the coupling of general tertiary systems using nickel catalysis. The scope of this operationally simple method is broad, and it can be used to simplify the synthesis of medicinally relevant motifs bearing quaternary centers.
Direct cross-coupling between an arylzincreagent and an arylhalide was accomplished without any externalcatalyst, enabling efficient and selective formation of the corresponding biaryl compound with broad functional group compatibility.