Synthesis of Novel 1-(1,5-Diaryl-1,10b-Dihydropyrrolo- [1,2-A][1,2,4]Triazolo[3,4-C]Pyrazin-3-Yl)Ethanones Via 1,3-Dipolar Cycloaddition of Nitrilimine

The 1,3-dipolar cycloaddition of nitrilimine, generated in situ from (Z)-N-aryl-2-oxopropanehydrazonoyl bromide and Et3N, to 3-arylpyrrolo[ 1,2-a]pyrazine afforded novel 1-(1,5-diaryl-1,10b-dihydropyrrolo[1,2-a][1,2,4]triazolo[3,4-c]pyrazin-3-yl)ethanones in moderate yields. The structures of all the products were characterized thoroughly by NMR, IR, and HRMS.