Other Variations of Fischer Indole Synthesis

The Borsche-Drechsel carbazole synthesis is simply a Fischer indoUzation involving cyclohexanones, followed by oxidation of the tetrahydrocarbazole to a carbazole [144-147]. For reviews, see Campbell and Barclay [148] and Fultz [149]. Examples appear in the Applications section. 

The Bucherer carbazole synthesis is the reaction of aromatic phenols, typically naphthols, with phenylhydra-zine to form the corresponding phenylhydrazone via the naphthol tautomer [150, 151]. Bucherer was an early 

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