Nitesh Kumar Nandwana

Synthesis of aza-fused isoquinolines through domino cross-aldol condensation and palladium-catalyzed intramolecular direct arylation.

A straightforward method has been developed for the synthesis of aroyl-substituted imidazo-/benzimidazo-fused isoquinolines. The cascade reaction proceeds via a cross-aldol condensation of 2-(1H-imidazol-1-yl/benzimidazolyl-1-yl)-1-arylethanones and 2-bromobenzaldehyde followed by palladium-catalyzed intramolecular C-H functionalization. This approach offers a simple and efficient alternative one-pot protocol for the assembly of imidazo/benzimidazo[2,1-a]isoquinolines in moderate to good yields.

Copper-catalyzed synthesis of quinoline derivatives via tandem Knoevenagel condensation, amination and cyclization

A novel regioselective synthesis of 2-aminoquinolines and 2-arylquinoline-3-carbonitriles is described via copper-mediated tandem reaction. Formation of substituted quinolines involves Knoevenagel condensation of ortho-bromobenzaldehyde with active methylene nitriles followed by copper-catalyzed reductive amination and intramolecular cyclization.

Metal-Free Synthesis of Aminomethylated Imidazoheterocycles: Dual Role of tert-Butyl Hydroperoxide both as an Oxidant and Methylene Source

A novel and efficient aminomethylation approach has been developed for the regioselective functionalization of imidazoheterocycles under metal-free conditions. A wide range of imidazoheterocycles and 2/4-aminoazaheterocycles successfully provided corresponding aminomethylated imidazoheterocycles in moderate to excellent (33-80%) yields. The isotopic labelling study suggested that TBHP played a dual role as both an oxidant and a methylene source in this transformation. The developed protocol follows a radical pathway which is supported by radical trapping experiments.