Benzo tropone synthesis

Fischer indole synthesis to cyclohexanone-2-troponylhydrazone and dehydrogenation of the product to indolo[2,3-h]tropone the 8- and 10-isopropyl-, and 7-bromo-analogues, were also prepared. Treatment of the 2-troponylhydrazones of cyclo-heptanone and JV-benzylpiperidinone with acid gave analogous products. Tndolo[2,3-h]tropone was converted into benzo[h]-l-aza-azulene. ... 

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