Synthesis 1991; 1991(10): 871-878
DOI: 10.1055/s-1991-26597
paper
© Georg Thieme Verlag, Rüdigerstr. 14, 70469 Stuttgart, Germany. All rights reserved. This journal, including all individual contributions and illustrations published therein, is legally protected by copyright for the duration of the copyright period. Any use, exploitation or commercialization outside the narrow limits set by copyright legislation, without the publisher's consent, is illegal and liable to criminal prosecution. This applies in particular to photostat reproduction, copying, cyclostyling, mimeographing or duplication of any kind, translating, preparation of microfilms, and electronic data processing and storage.

Preparation of Indoles and Oxindoles from N-(tert-Butoxycarbonyl)-2-alkylanilines

Robin D. Clark* , Joseph M. Muchowski, Lawrence E. Fisher, Lee A. Flippin, David B. Repke, Michel Souchet
  • *Syntex Research, Institute of Organic Chemistry, 3401 Hillview Ave., Palo Alto, CA 94304, USA
Further Information

Publication History

Publication Date:
29 April 2002 (online)

Treatment of dilithiated N-(tert-butoxycarbonyl)anilines 1 with dimethylformamide or carbon dioxide furnishes intermediates 3, 5, that are easily converted to N-(tert-butoxycarbonyl)indoles 4 and oxindoles (indol-2(3H)-ones, 7), respectively. Condensation of dilithiated 1 with N-methoxy-N-methylamides provides ketones 9 which are cyclized upon trifluoroacetic acid treatment to either 2-substituted 1-(tert-butoxycarbonyl)indoles 10 or 2-substituted indoles 11 depending on the reaction time. This general methodology has been applied to efficient synthesis of 1,2-alkyl-bridged indoles 12, 1,3,4,5-tetrahydrobenz[c,d]indole (16), 2a,3,4,5-tetrahydrobenz [c,d]indol-2(1H)-one (18), and 1-(tert-butoxycarbonyl) -1H-pyrrolo[2,3-b]pyridine (21).

    >