Nickel-Catalyzed Kumada Cross-Coupling Reactions of Benzylic Sulfonamides

Herein, we report a Kumada cross-coupling reaction of benzylic sulfonamides. The scope of the transformation includes acyclic and cyclic sulfonamide precursors that cleanly produce highly substituted acyclic fragments. Preliminary data are consistent with a stereospecific mechanism that allows for a diastereoselective reaction.

Electrochemical Synthesis of Isoxazolines: Method and Mechanism

An electrochemical method for the green and practical synthesis of a broad range of substituted isoxazoline cores is presented. Both aryl and more challenging alkyl aldoximes are converted to the desired isoxazoline <i>via</i> an electrochemically enabled regio- and diastereoselective reaction with electron-deficient alkenes. Additionally, <i>in-situ</i> reaction monitoring methods compatible with electrochemistry equipment have also been developed in order to probe the reaction pathway. Supporting analyses from kinetic (time-course) modeling and density functional theory support a stepwise, radical-mediated mechanism, and discounts hypothesized involvement of closed shell [3+2] cycloaddition pathways.

Electrochemical Synthesis of Isoxazolines: Method and Mechanism

An electrochemical method for the green and practical synthesis of a broad range of substituted isoxazoline cores is presented. Both aryl and more challenging alkyl aldoximes are converted to the desired isoxazoline <i>via</i> an electrochemically enabled regio- and diastereoselective reaction with electron-deficient alkenes. Additionally, <i>in-situ</i> reaction monitoring methods compatible with electrochemistry equipment have also been developed in order to probe the reaction pathway. Supporting analyses from kinetic (time-course) modeling and density functional theory support a stepwise, radical-mediated mechanism, and discounts hypothesized involvement of closed shell [3+2] cycloaddition pathways.

Acetylene-based two-step diastereoselective synthesis of bridgehead dihydro-oxadiazines using ketones and hydrazine as the only reactants

Bridgehead dihydro-1,3,4-oxadiazines are synthesized by the acid-catalyzed diastereoselective reaction of hydrazine with 6,8-dioxabicyclo[3.2.1]octanes, the products of the superbase-promoted self-organization of acetylene with ketones.

Base-Catalyzed Tandem Cyclization: Diastereoselective Access to the 3,4-Dihydroisoquinolin-2(1H)-one Core

A novel, one-pot reaction for the synthesis of 3,4-dihydroisoquinolin-2(1H)-one derivatives is developed via a base-mediated three-component reaction of ninhydrin, aniline and acetylenic esters. This diastereoselective reaction takes place in methanol at 70 °C under transition-metal-free conditions, and direct construction of the C–N and C–C bonds is readily achieved via tandem cyclization. These cyclic frameworks are resourceful small molecular keys to many natural products.