intermediates have been widely applied in the synthesis of functionalized allenes, but reactions involving allenyl radicals have been less studied and limited successful examples have been realized mainly by transition metal catalysis. We herein demonstrate the generation of allenyl radicals by N-heterocycliccarbene (NHC) organocatalysis and their applications in the three-component radical relay 1,4-alkylcarbonylation
Selective Dehydrogenative Acylation of Enamides with Aldehydes Leading to Valuable β-Ketoenamides
作者:Rui-Hua Liu、Zhen-Yao Shen、Cong Wang、Teck-Peng Loh、Xu-Hong Hu
DOI:10.1021/acs.orglett.9b04495
日期:2020.2.7
We have presented a unique example of dehydrogenative acylation of enamides with aldehydes enabled by an earth-abundant iron catalyst. The protocol provides the straightforward access to valuable β-ketoenamides with ample substrate scope and excellent functional group tolerance. Notably, distinct C-H acylation of enamide rather than at N-H moiety site occurs with absolute Z-selectivity was observed
Highly <i>E</i>-Selective Synthesis of α-Fluoro-β-arylalkenyl Sulfones from <i>gem</i>-Difluoroalkenes with Sodium Sulfinates
作者:Yuxiu Li、Xiangqian Li、Xiaowei Li、Dayong Shi
DOI:10.1021/acs.joc.1c00490
日期:2021.5.7
The straightforward synthesis of α-fluoro-β-arylalkenyl sulfones under transition-metal- and base-free conditions has been described, which displays broad functional group compatibility and high stereoselectivity. In particular, the strategy is also applied to the late-stage modification of complex natural products and drugs.
N-Heterocyclic Carbene/Magnesium Cocatalyzed Radical Relay Assembly of Aliphatic Keto Nitriles
作者:Lei Chen、Shiyi Jin、Jian Gao、Tongtong Liu、Yuebo Shao、Jie Feng、Kangyi Wang、Tao Lu、Ding Du
DOI:10.1021/acs.orglett.0c03883
日期:2021.1.15
magnesium cocatalyzed three-component acylcyanoalkylation of alkenes with cycloketone oxime esters and aldehydes is presented. This method displayed good scope generality, providing a transition-metal- and photoredox-free pathway to access various multifunctionalized aliphatic keto nitrile structures undermildreactionconditions. Moreover, this strategy is supposed to follow a radical relay mechanism via
Electrochemical Difunctionalization of Alkenes by a Four‐Component Reaction Cascade Mumm Rearrangement: Rapid Access to Functionalized Imides
作者:Xiaofeng Zhang、Ting Cui、Xin Zhao、Ping Liu、Peipei Sun
DOI:10.1002/anie.201913332
日期:2020.2.24
transfer. Inexpensive, commercially available arylethylenes, aryl or heterocyclic acids, acetonitrile, and alcohols were used as substrates. A wide range of aryl acids and alcohols were tolerated and provided imides in satisfactory yields. Subsequent hydrolysis of imides could be utilized to synthesize valuable amides and β-amino alcohol derivatives.