I. A. Danish, K. Prasad
2005
Citations
0
Influential Citations
6
Citations
Journal
Collection of Czechoslovak Chemical Communications
Abstract
2-Benzylidene-1,2,3,4-tetrahydrocarbazol-1-ones 1 , synthons easily accessible from the corresponding 1,2,3,4-tetrahydrocarbazol-1-ones, were utilized in the synthesis of fused carbazoles. In accordance, the reaction of 1 with malononitrile yielded pyrano[2,3- a ]carbazoles 2a and 2d or pyrido[2,3- a ]carbazoles 2b , 2c and 2e . The reaction of 1 with thiocarbohydrazide or thiosemicarbazide under basic conditions afforded pyridazino[3,4- a ]carbazoles 3 or thiol substituted pyridazino[3,4- a ]carbazoles 4 , respectively, in good yields. The formation of the hitherto unknown compounds was well supported by plausible mechanisms. The products formed were characterized by IR, 1 H NMR, 13 C NMR, mass spectral methods and by elemental analysis.