Copper‐Catalyzed Difluoromethylation of Alkyl Iodides Enabled by Aryl Radical Activation of Carbon–Iodine Bonds
作者:Aijie Cai、Wenhao Yan、Chao Wang、Wei Liu
DOI:10.1002/anie.202111993
日期:2021.12.20
An aryl radical activation strategy has been developed that can engage unactivated alkyliodides in copper-catalyzed Negishi-type cross-coupling reactions. The strategy is based on the largely overlooked yet highly efficient reactivity of aryl radicals to abstract iodine atoms from alkyliodides.
The first catalyticoxygenativeallylictransposition of unactivated alkenes into enones has been developed using an oxoammoniumsalt as the catalyst. This reaction converts various tri- and trans-disubstituted alkenes into their corresponding enones with transposition of their double bonds at ambient temperature in good yields. The use of a less-hindered azaadamantane-type oxoammoniumsalt as the catalyst
使用氧代铵盐作为催化剂,已开发出未活化的烯烃向烯酮的第一个催化氧化烯丙基转移。该反应将各种三和反双取代的烯烃转化成其相应的烯酮,并在环境温度下以双键的换位以良好的收率。使用较少受阻的氮杂金刚烷型氧铵盐作为催化剂,并使用两种不同的化学计量氧化剂(即碘代苯二乙酸盐和单过氧邻苯二甲酸镁六水合物(MMPP·6 H 2 O))的组合,对于有效促进烯酮的形成至关重要。
Copper-Catalyzed Cross-Coupling of Silicon Pronucleophiles with Unactivated Alkyl Electrophiles Coupled with Radical Cyclization
A copper-catalyzedC(sp3)-Si cross-coupling of aliphatic C(sp3)-I electrophiles using a Si-B reagent as the silicon pronucleophile is reported. The reaction involves an alkyl radical intermediate that also engages in 5-exo-trig ring closures onto pendant alkenes prior to the terminating C(sp3)-Si bond formation. Several Ueno-Stork-type precursors cyclized with excellent diastereocontrol in good yields
Aryl sulfonium salt electron donor-acceptor complexes for halogen atom transfer: Isocyanides as tunable coupling partners
作者:Huaibo Zhao、Valentina D. Cuomo、James A. Rossi-Ashton、David J. Procter
DOI:10.1016/j.chempr.2024.01.020
日期:2024.4
(electron donor-acceptor) complexes provides a mild platform for aryl-radical-mediated halogen atom transfer activation of a wide range of functionalized alkyl iodides, including tertiary alkyl iodides. Using an aryl sulfonium salt with carbonate as an inexpensive donor for EDA complex formation, the general reaction platform has been applied in a divergent, metal-free photochemical approach to nitriles