Cu-Catalyzed Methylenation of Alcohols with N-Methyl Amide as a Sustainable Methylene Reagent.

Herein, we report a new approach to methylenation of alcohols using N-methyl amide as a sustainable methylene reagent; the N-methyl delivers the methylene group. This new reagent is easily prepared and stable to both air and moisture. Furthermore, the final byproduct of this methylene reagent can be recycled in excellent yields and then reused in methylenation reactions upon treating with CH3I.

Electrochemical Activation of Nitromethane to Construct Isoxazoline Aldoximes.

Activation of nitromethane to endow new reactivity is an interesting and meaningful but also challenging topic. Herein, we report an electrochemical activation of nitromethane to serve as both the heterocyclic skeleton and oxime sources for the construction of isoxazoline aldoximes. The isoxazoline aldoximes that are prepared by four steps with the reported strategy are synthesized in a single step from low-cost and readily available nitromethane and olefins with moderate to excellent yields under our electrochemical conditions. The reaction also takes advantage of high atom-economy and E-selectivity. Moreover, the mechanism is studied by control experiments, a kinetic isotope effect (KIE) study, cyclic voltammogram (CV) experiments, and density functional theory (DFT) calculations. The mechanistic results reveal that nitromethane may be activated under electrochemical conditions to deliver a 1,2,5-oxadiazole 2-oxide intermediate, which undergoes [3+2] cycloaddition with olefins to yield isoxazoline aldoximes.