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A cycloisomerization/Friedel-Crafts alkylation strategy for the synthesis of pyrano[3,4-b]indoles.

ABSTRACT: The synthesis of pyrano[3,4-b]indoles is described. The reaction sequence involves Sonogashira coupling of dihydropyran propargyl ether scaffolds with iodoanilines to afford intermediate indoles. Lewis acid-catalyzed ionization of the dihydropyrans, followed by intramolecular C3 alkylation of the indole, provides the title compounds.

SUBMITTER: Medeiros MR

PROVIDER: S-EPMC3146574 | biostudies-literature | 2011 Aug

REPOSITORIES: biostudies-literature

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A cycloisomerization/Friedel-Crafts alkylation strategy for the synthesis of pyrano[3,4-b]indoles.

Medeiros Matthew R MR Schaus Scott E SE Porco John A JA

Organic letters 20110708 15

The synthesis of pyrano[3,4-b]indoles is described. The reaction sequence involves Sonogashira coupling of dihydropyran propargyl ether scaffolds with iodoanilines to afford intermediate indoles. Lewis acid-catalyzed ionization of the dihydropyrans, followed by intramolecular C3 alkylation of the indole, provides the title compounds. ...[more]

PMID: 21740020

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