High-Throughput Screening of the Asymmetric Decarboxylative Alkylation Reaction of Enolate-Stabilized Enol Carbonates Asymmetric Decarboxylative Alkylation Reaction of Enolate-Stabilized Enol Carbonates

نویسندگان

  • N T. McDougal
  • Scott C. Virgil
  • Brian M. Stoltz
  • Katharine Schlinger
چکیده

SYNLETT 2010, No. 11, pp 1712–1716xx.xx.2010 Advanced online publication: 14.06.2010 DOI: 10.1055/s-0030-1258094; Art ID: Y00510ST © Georg Thieme Verlag Stuttgart · New York Abstract: The use of high-throughput screening allowed for the optimization of reaction conditions for the palladium-catalyzed asymmetric decarboxylative alkylation reaction of enolate-stabilized enol carbonates. Changing to a nonpolar reaction solvent and to an electron-deficient PHOX derivative as ligand from our standard reaction conditions improved the enantioselectivity for the alkylation of a ketal-protected,1,3-diketone-derived enol carbonate from 28% ee to 84% ee. Similar improvements in enantioselectivity were seen for a b-keto ester derived and an a-phenyl cyclohexanonederived enol carbonate.

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High-Throughput Screening of the Asymmetric Decarboxylative Alkylation Reaction of Enolate-Stabilized Enol Carbonates.

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تاریخ انتشار 2010