Letters in Organic Chemistry

Author(s): Isidro M. Pastor, Rosario Torregrosa and Miguel Yus

DOI: 10.2174/157017810791514850

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Isoprene-Mediated Lithiation of 1-Alkylimidazoles: Chiral Induction of the Alkyl Substituent

Page: [373 - 376] Pages: 4

  • * (Excluding Mailing and Handling)

Abstract

The isoprene-mediated lithiation of imidazoles bearing a secondary alkyl substituent at the nitrogen (7, 8 and 13) and the subsequent nucleophilic addition to different electrophiles allows the preparation of the corresponding 2- functionalized imidazoles 10, 11 and 14. The presence of a stereogenic center in the alkyl substituent induces diastereoselection during the nucleophilic addition step with a prochiral electrophile (i.e. pivalaldehyde), producing the expected imidazole derivative with excellent overall yield, but low de (up to 26%).

Keywords: Isoprene-mediated lithiation, imidazole derivatives, nucleophilic addition, lithium