Organocatalytic Vinyl and Friedel−Crafts Alkylations with Trifluoroborate Salts
作者:Sandra Lee、David W. C. MacMillan
DOI:10.1021/ja0767480
日期:2007.12.1
pathway. Boronic acids can also be employed as viable π-nucleophiles for these asymmetric conjugate additions provided that in situ activation to the corresponding boronate species is accomplished. While BF3K salts are routinely employed in transition metal catalysis, to our knowledge, this is the first use of this activation group for organic catalysis or Friedel−Crafts alkylations.
Asymmetric Organocatalytic Formal Alkynylation and Alkenylation of α,β-Unsaturated Aldehydes
作者:Martin Nielsen、Christian Borch Jacobsen、Márcio W. Paixão、Nicole Holub、Karl Anker Jørgensen
DOI:10.1021/ja903920j
日期:2009.8.5
stereoselective organocatalytic one-pot protocol for the formal alkynylation and alkenylation of alpha,beta-unsaturated aldehydes using novel chemistry based on beta-keto heterocyclic sulfones is presented. The organocatalytic step is catalyzed by a prolinol derivative and allows for the formation of important optically active compounds. Further transformations of the beta-keto heterocyclic sulfone moiety,