Zinc Carbenoid-Mediated Chain Extension: Preparation of α,β-Unsaturated-γ-keto Esters and Amides
Matthew D. Ronsheim and Charles K. Zercher*
*Department of Chemistry, University of New Hampshire, Durham, New Hampshire 03824, Email: ckzchrista.unh.edu
M. D. Ronsheim, C. K Zercher, J. Org. Chem., 2003, 68, 4535-4538.
DOI: 10.1021/jo026299g (free Supporting Information)
A zinc carbenoid-mediated chain extension of β-dicarbonyl compounds provides access to α,β-unsaturated-γ-keto esters and amides with complete E selectivity via an intermediate zinc enolate, which is treated sequentially with iodine and DBU.
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W. Lin, R. J. McGinness, E. C. Wilson, C. K. Zercher, Synthesis, 2007, 2404-2408.