| Abstract
| - The double N-arylation of primary amines with 2,2‘-biphenylylene ditriflates was investigated forthe synthesis of multisubstituted carbazoles. Palladium complexes supported by 2-dicyclohexylphosphino-2‘-methylbiphenyl or Xantphos [4,5-bis(diphenylphosphino)-9,9-dimethylxanthene] werefound to be efficient catalysts for the reaction. The catalysts allow the use of anilines with anelectron-donating or electron-withdrawing substituent and multisubstituted 2,2‘-biphenylyleneditriflates as substrates. Ammonia equivalents, such as O-tert-butyl carbamate, are also employableas a nitrogen source to give the N-protected carbazoles which can easily give the correspondingN-unsubstituted carbazoles after deprotection. By using this methodology, a carbazole alkaloid,mukonine, is synthesized in 40% yield for five steps, in comparable efficiency to the recentprecedents.
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