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A simple and convenient multi-component domino reaction has been described for the synthesis of novel spirofuran-indenoquinoxaline derivatives. Products were obtained by a three-component condensation reaction between ninhydrin, aromatic 1,2-diamines and dialkyl ethynedicarboxylates in the presence of a catalytic amount of triphenylphosphine in CH 2 Cl 2 at ambient temperature in excellent yields. This one-pot process produces biologically and pharmacologically significant heterocycles with the formation of five new bonds (one CC , two C=N and two CO) and two new rings in a single operation.

Theophylline-catalyzed efficient and environmentally benign procedure for the diastereoselective synthesis of trans-1,2-dihydrobenzo[a]furo[2,3-c]phenazines with pyridinium ylide assisted domino reaction in water.

Superparamagnetic nanoparticles of modified vitamin B3 (Fe3O4@Niacin) represent a new, efficient and green biocatalyst for the one‐pot synthesis of 2‐amino‐3‐cyanopyridine derivatives via four‐component condensation reaction between aldehydes, ketones, malononitrile, and ammonium acetate under microwave irradiation in water. This new magnetic organocatalyst was easily isolated from the reaction mixture by magnetic decantation using an external magnet and reused at least six times without significant degradation in the activity. The catalyst was fully characterized by FT‐IR, XRD, SEM, VSM, UV–Vis, DLS and EDS. Excellent yield, very short reaction time (7–10 min), operational simplicity, easy work‐up procedure, avoidance of hazardous or toxic catalysts and organic solvents are the main advantages of this green methodology which makes it more economic than the other conventional methods.