Department of Chemistry, University of California, Berkeley, CA 94720, USA.
Proc Natl Acad Sci U S A. 2013 Aug 20;110(34):13729-33. doi: 10.1073/pnas.1304346110. Epub 2013 Aug 6.
We report a catalytic enantioselective electrophilic fluorination of alkenes to form tertiary and quaternary C(sp3)-F bonds and generate β-amino- and β-aryl-allylic fluorides. The reaction takes advantage of the ability of chiral phosphate anions to serve as solid-liquid phase transfer catalysts and hydrogen bond with directing groups on the substrate. A variety of heterocyclic, carbocyclic, and acyclic alkenes react with good to excellent yields and high enantioselectivities. Further, we demonstrate a one-pot, tandem dihalogenation-cyclization reaction, using the same catalytic system twice in series, with an analogous electrophilic brominating reagent in the second step.
我们报告了一种催化对映选择性亲电氟化烯烃的方法,可形成叔碳和季碳 C(sp3)-F 键,并生成 β-氨基-和 β-芳基-烯丙基氟化物。该反应利用手性磷酸阴离子作为固-液相转移催化剂的能力,并与底物上的导向基团形成氢键。各种杂环、碳环和无环烯烃以良好到优异的收率和高对映选择性反应。此外,我们还展示了一种一锅法、串联的双卤化-环化反应,在第二步中使用相同的催化体系两次串联,使用类似的亲电溴化试剂。