Synthesis of 3-aminooxindoles via acid-promoted cyclization of α-imino-N-arylamides and α-azido-N-arylamides

One-Pot, Five-Component Condensation Reaction of Isatin, Secondary Amines, Malononitrile, Alcohols, and Molecular Oxygen to Access 3-Functionalized 2-Oxindoles

An efficient five-component condensation reaction of isatin, malononitrile, secondary amines, alcohols, and molecular oxygen was discovered. The reaction was performed in a one-pot fashion, and it does not require any metal catalyst. It gives straightforward access to structurally diverse 2-oxo-3-aminoindoline-3-carboxylates in moderate yields (70-88%). The scope of the reaction was successfully demonstrated by synthesizing a series of 3-functionalized 2-oxindoles by varying the isatin, amine, and alcohol components.

Reductive Alkenylation of Ketimines via Hydride Transfer from Aldehydes

The first direct N-heterocyclic carbene (NHC)-catalyzed preparation of allylic amines bearing a quaternary center (α-tertiary amine) from isatin-derived ketimines in the presence of vinyl selenones and aldehydes is reported. This multicomponent reaction is expected to proceed via unprecedented in situ reduction of imines through a hydride transfer from the aldehydes.