Multicomponent reaction of chalcones, malononitrile and DMF leading to γ-ketoamides.

An efficient synthesis of γ-ketoamides was developed by the one-pot multicomponent reaction of chalcones, malononitrile and DMF (as both the reactant and solvent) in the presence of NaOH (3.0 equiv.). The reaction features high atom economy, easily available starting materials, operational simplicity, and good tolerance with diverse functional groups.

Synthesis of spiro[isoquinolinone-4,2'-oxiranes] and isoindolinones via a multicomponent reaction of 2-acetyl-oxirane-2-carboxamides, arylaldehydes and malononitrile.

Efficient synthesis of spiro[isoquinolinone-4,2'-oxiranes] was achieved based on a multicomponent one-pot reaction of readily available cis-2-acetyl-oxirane-2-carboxamides, arylaldehydes and malononitrile at room temperature. However, in the reaction with trans-2-acetyl-oxirane-2-carboxamide substrates, 3-iminoisoindolinones were obtained in moderate to high yields.

Halonium-initiated double oxa-cyclization cascade as a synthetic strategy for halogenated furo[3,2-c]pyran-4-ones.

The reaction of 1-alkenoylcyclopropane carboxylic acids with NBS or NIS was investigated, which provides an efficient route to biologically important 7-halogenated furo[3,2-c]pyran-4-ones in a one-pot transformation. The major pathway for the formation of the O-O heterocycles was proposed as a halo-oxa-cyclization, HBr elimination, cyclopropane ring-opening and recyclization (intramolecular oxa-cyclization), and bromination cascade. The double-oxa-cyclization represents a novel synthetic strategy towards functionalized furo[3,2-c]pyranones.