1 -Hydroxy-3-methylcarbazole total synthesis

Murakami et al. reported the total synthesis of 1-hydroxy-3-methylcarbazole (23) and murrayafoline A (7) by classical Fischer indolization of the O-methanesulfonyl phenylhydrazone derivative 614 (575). The compound 614 was prepared from the corresponding aminophenol 612 via 2-hydrazino-5-methylphenol p-toluenesulfonate... 

Murakami et al. reported (575) a total synthesis of murrayaquinone A (107) by oxidation of l-hydroxy-3-methylcarbazole (23) with Fremy s salt, as previously described by Martin and Moody (632). The hydroxycarbazole 23 required for this synthesis was obtained via the Fischer indolization of the O-methanesulfonyl phenylhydrazone 614 (575) (see Scheme 5.38). The oxidation of l-hydroxy-3-methylcarbazole (23) with Fremy s salt afforded murrayaquinone A (107) as the major product, along with a 5% yield of isomeric carbazole-l,2-quinone 876 (575) (Scheme 5.108). 

Bringmann et al. reported the first total synthesis and stereoanalysis of bismurrayaquinone-A (215) by oxidation of bis(0-demethylmurrayafoline A) (204) (661). The required monomer, l-hydroxy-3-methylcarbazole (O-demethylmurrayafoline... 

We reported the first total synthesis of l,T-bis(2-hydroxy-3-methylcarbazole) (213) using our molybdenum-mediated construction of the carbazole framework (560). The required monomer, 2-hydroxy-3-methylcarbazole (52), was obtained in three steps, and 22% overall yield, starting from dicarbonyl(ri -cyclohexa-l,3-diene)(ri -cyclopentadienyl)molybdenum hexafluorophosphate (663) and 3-meth-oxy-4-methylaniline (655) (560) (see Scheme 5.52). Finally, oxidative coupling of the monomer 52 using p-chloranil afforded l,T-bis(2-hydroxy-3-methylcarbazole) (213) in 38% yield (560) (Scheme 5.167). 

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