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, 1H NMR, 13C NMR, mass spectral methods and by elemental analysis.
2-苄基亚甲基-1,2,3,4-四氢咔唑-1-酮1,易于从相应的1,2,3,4-四氢咔唑-1-酮合成物中获得的合成子,在合成融合咔唑化合物中得到应用。相应地,1与马来酸二腈反应生成吡喃并[2,3-a]咔唑2a和2d,或吡啶并[2,3-a]咔唑2b、2c和2e。1与硫代甲酰肼或硫代脲在碱性条件下反应生成吡啶并[3,4-a]咔唑3或硫代取代的吡啶并[3,4-a]咔唑4,收率较高。对迄今为止未知的化合物的形成得到了合理的机制支持。产物通过红外光谱、1H核磁共振、13C核磁共振、质谱方法和元素分析进行了表征。