Catalyticenantioselective chemical reactions involving highly reactive radical species remain largely unexplored. We report herein for the first time a novel enantioselective radical ring-opening cyanation of redox-active oxime esters by dual photoreodox and copper catalysis. This mild protocol shows good functional group tolerance and broad substrate scope, producing a wide range of optically active
Cu-Catalyzed Redox-Neutral Ring Cleavage of Cycloketone <i>O</i>-Acyl Oximes: Chemodivergent Access to Distal Oxygenated Nitriles
作者:Wenying Ai、Yaqian Liu、Qian Wang、Zhonglin Lu、Qiang Liu
DOI:10.1021/acs.orglett.7b03707
日期:2018.1.19
chemodivergent copper-catalyzed ring opening of cycloketone oximes via radical-mediated C–C bond cleavage under redox-neutral conditions is described. This method allows the divergent synthesis of γ- and δ-acyloxylated, alkoxylated, and hydroxylated nitriles while avoiding the use of toxic cyanide reagents. Moreover, these reactions proceed under very mildconditions with good functional group tolerance
Rh(III)-Catalyzed Mild Coupling of Nitrones and Azomethine Imines with Alkylidenecyclopropanes via C–H Activation: Facile Access to Bridged Cycles
作者:Dachang Bai、Teng Xu、Chaorui Ma、Xin Zheng、Bingxian Liu、Fang Xie、Xingwei Li
DOI:10.1021/acscatal.8b00746
日期:2018.5.4
activation of nitrones and azomethine imines in the context of dipolar addition with alkylidenecyclopropanes (ACPs) have been realized. By taking advantage of the ring strain in ACPs, the reaction with aryl nitrones delivered bridged [3.2.1] bicyclicisoxazolidines, and reaction with azomethine imines afforded bridged tricyclic pyrazolones under the same conditions, where both the nitrone and azomethine
Cobalt‐Catalyzed Tandem C−H Activation/C−C Cleavage/C−H Cyclization of Aromatic Amides with Alkylidenecyclopropanes
作者:Mingliang Li、Fuk Yee Kwong
DOI:10.1002/anie.201801706
日期:2018.5.28
A cobalt‐catalyzed chelation‐assisted tandem C−Hactivation/C−C cleavage/C−H cyclization of aromatic amides with alkylidenecyclopropanes is reported. This process allows the sequential formation of two C−C bonds, which is in sharp contrast to previous reports on using rhodium catalysts for the formation of C−N bonds. Here the inexpensive catalyst system exhibits good functional‐group compatibility
Rh(III)-Catalyzed Stereoselective C–C Bond Cleavage of ACPs with <i>N</i>-Phenoxyacetamides: The Critical Role of the Nucleophilic Directing Group
作者:Anurag Singh、Arnab Dey、Chandra M. R. Volla
DOI:10.1021/acs.joc.1c01135
日期:2021.8.6
phenols in nonpolar solvents, whereas [3 + 2]-annulation leading to dihydrobenzofurans was realized in polar fluorinated solvents. It was observed that the nucleophilic directing group controls the elimination of β-carbon and so plays a vital role for achieving high stereoselectivities. The synthetic utility of the dienylation and annulation was demonstrated by carrying out gram scale reactions and further