Microwave‐assisted Stereoselective Synthesis

Abstract

Microwave‐assisted organic synthesis (MAOS) is now recognized as an extremely powerful technology. Dielectric heating, i.e., heating by microwave irradiation, dramatically differs from conductive heating because it involves core heating by direct interaction of reactants and/or solvents with the microwave electromagnetic field. As a result, elevated reaction temperatures can be reached in minutes or even seconds, which usually translates in cleaner and faster reactions. Recently, the technology has successfully been applied to stereoselective organic synthesis. The authors' opinion is that MAOS will soon become the primary choice for thermal activation of organic processes and, as the authors' experienced, will undoubtedly facilitate the discovery of new stereoselective reactions.

Direct oxidation of N-ynylsulfonamides into N-sulfonyloxoacetamides with DMSO as a nucleophilic oxidant

“…We envisioned that nucleophilic zwitterionic DMSO could serve as a nucleophilic oxidant in the reaction with relatively electron-deficient N -ynylsulfonamides under microwave-assisted conditions because microwave irradiation can accelerate some organic reactions. 15 Herein, we present a direct and efficient oxidation of N -arylethynylsulfonamides into α-ketoimides under the microwave irradiation without the addition of any other electrophilic activating reagents (such as I 2 , NIS, Cu(CH 3 CN) 4 PF 6 and so on) and external oxidants (for instant, N -oxide, O 2 ).…”