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Synlett 2013; 24(9): 1133-1136
DOI: 10.1055/s-0033-1338385
letter
© Georg Thieme Verlag Stuttgart · New York

Deprotonative Metalation of Chlorothiophene with Grignard Reagents and Catalytic cis-2,6-Dimethylpiperidine under Mild Conditions

Shunsuke Tamba
Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan   Fax: +81(78)8036181   Email: amori@kobe-u.ac.jp
,
Kenji Ide
Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan   Fax: +81(78)8036181   Email: amori@kobe-u.ac.jp
,
Keisuke Shono
Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan   Fax: +81(78)8036181   Email: amori@kobe-u.ac.jp
,
Atsushi Sugie
Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan   Fax: +81(78)8036181   Email: amori@kobe-u.ac.jp
,
Atsunori Mori*
Department of Chemical Science and Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501, Japan   Fax: +81(78)8036181   Email: amori@kobe-u.ac.jp
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Further Information

Publication History

Received: 23 February 2013

Accepted after revision: 21 March 2013

Publication Date:
12 April 2013 (online)

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Abstract

Deprotonative metalation of chlorothiophene takes place with a catalytic amount of cis-2,6-dimethylpiperidine (DMP) and an alkyl Grignard reagent at room temperature for three hours to give the corresponding thienyl Grignard reagent. Polymerization leading to head-to-tail-type poly(3-substituted thiophene) with the thus metalated chlorothiophene proceeds in the presence of a nickel catalyst bearing an N-heterocyclic carbene (NHC) ligand. Palladium-catalyzed cross-coupling reaction with aryl bromides also gives arylated thiophenes in good to excellent yields while the C–Cl bond remains intact.

Key words

chlorothiophene - palladium - nickel - cross-coupling - Grignard reagent

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  • References and Notes

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