Synthesis 2014; 46(01): 35-41
DOI: 10.1055/s-0033-1338523
practical synthetic procedures
© Georg Thieme Verlag Stuttgart · New York

Regioselective Direct C–H Alkylation of NH Indoles and Pyrroles by a Palladium/Norbornene-Cocatalyzed Process

Lei Jiao
Lehrstuhl für Organische Chemie I and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany   Fax: +49(89)28913315   Email: [email protected]
,
Thorsten Bach*
Lehrstuhl für Organische Chemie I and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstr. 4, 85747 Garching, Germany   Fax: +49(89)28913315   Email: [email protected]
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Further Information

Publication History

Received: 29 July 2013

Accepted: 03 August 2013

Publication Date:
17 September 2013 (online)


Abstract

Nitrogen-containing heterocycles, including 1H-indoles and electron-deficient 1H-pyrroles, undergo a palladium/norbornene-cocatalyzed regioselective alkylation at the C–H bond adjacent to the NH group. A primary alkyl halide is used as the electrophile and the reaction proceeds smoothly under mild conditions to give 2-alkyl-1H-indoles and 2-substituted or 2,3-disubstituted 5-alkyl-1H-pyrroles in good yields.

 
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