Dayun Huang

Synthesis of N-Sulfonyl Arylaldimines Developed by Retesting an Old Process

By simply heating the mixture of an arylaldehyde and a sulfonylisocyanate in a solvent or in neat form under catalyst- and additive-free conditions, the desired N-sulfonylimine was produced with the release of carbon dioxide. The method is characterized by its unique clean efficiency, convenience, and scalability, but it was reported to fail half a century ago.

Tandem synthesis of 3-halo-5-substituted isoxazoles from 1-copper(I) alkynes and dihaloformaldoximes.

A tandem synthesis of 3-halo-5-substituted isoxazoles has been developed from 1-copper(I) alkynes and dihaloformaldoximes under base-free conditions. Thus, 1,3-dipolar cycloaddition and all its drawbacks can now be avoided completely.

Tandem Synthesis of α-Diazoketones from 1,3-Diketones

A highly efficient synthesis of α-diazoketone was achieved by simply stirring the mixture of 1,3-diketone, TsN3, and MeNH2 in EtOH. It was a tandem reaction including a novel primary amine-catalyzed Regitz diazo transfer of 1,3-diketone and a novel primary amine-mediated C-C bond cleavage of 2-diazo-1,3-diketone.

Lewis acid-catalyzed tandem synthesis of 9-sulfonylamino- and 9-arylfluorenes

A Lewis acid-catalyzed three-step tandem synthesis of 9-arylfluorene was developed by simply heating a mixture of 2-formyl biphenyl, TsNCO and an arene. In the absence of arene, a two-step tandem synthesis of 9-sulfonylaminofluorene was achieved. These advances were mainly attributed to the discovery of an anhydrous synthesis of N-tosyl arylaldimines from TsNCO and arylaldehydes.