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Unusual Friedlander reactions: a route to novel quinoxaline-based heterocycles.

ABSTRACT: Acid catalyzed Friedlander reactions of a number of 2,3-dihydro-1H-cyclopenta[b]quinoxaline-1-ones with 2-aminobenzaldehyde yield, unexpectedly, 8H-indolo[3,2-a]phenazine and quinolino[2,3-c]cyclopentadienone[2,3-b]quinoxalines, the structures of derivatives of which were confirmed by X-ray crystallography. Easy routes to novel quinoxaline-based indoles, quinolones, and quinoxaline-1,4-dioxides are reported, and proposed mechanisms for the unexpected products are discussed.

SUBMITTER: Shoker TA

PROVIDER: S-EPMC3492540 | biostudies-literature | 2012 Jul

REPOSITORIES: biostudies-literature

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Unusual Friedlander reactions: a route to novel quinoxaline-based heterocycles.

Shoker Tharallah A TA Ghattass Khaled I KI Fettinger James C JC Kurth Mark J MJ Haddadin Makhluf J MJ

Organic letters 20120711 14

Acid catalyzed Friedlander reactions of a number of 2,3-dihydro-1H-cyclopenta[b]quinoxaline-1-ones with 2-aminobenzaldehyde yield, unexpectedly, 8H-indolo[3,2-a]phenazine and quinolino[2,3-c]cyclopentadienone[2,3-b]quinoxalines, the structures of derivatives of which were confirmed by X-ray crystallography. Easy routes to novel quinoxaline-based indoles, quinolones, and quinoxaline-1,4-dioxides are reported, and proposed mechanisms for the unexpected products are discussed. ...[more]

PMID: 22783916

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