Synthesis of Functionalized Azet-2(1H)-imines through [2+2] Cycloaddition of Imines and Ketenimines

The reaction between ketenimine intermediates, generated from terminal alkynes and sulfonyl azides, trichloroacetonitrile, and sodium arylsulfinates in N,N-dimethylformamide at room ­temperature affords N-[3-aryl(alkyl)-4-arylazet-2(1H)-ylidene]-arene(alkane)sulfonamides in moderate to good yields.