Lewis Acid-Promoted Friedel−Crafts Alkylation Reactions with α-Ketophosphate Electrophiles
作者:Austin G. Smith、Jeffrey S. Johnson
DOI:10.1021/ol100410k
日期:2010.4.16
The BF3·OEt2-promoted nucleophilicsubstitution of α-aryl-α-ketophosphates to afford α,α-diaryl ketone products is described. Electron-rich α-ketophosphates perform best, with electron-neutral and electron-poor substrates also tolerated. The reaction is tolerant of a range of aromatic, heteroaromatic, and nonaromatic nucleophiles, with yields ranging from 44% to 84%. Enantioenriched starting material
描述了BF 3 ·OEt 2促进的α-芳基-α-酮磷酸盐的亲核取代,以提供α,α-二芳基酮产物。富含电子的α-酮磷酸酯的性能最佳,同时还可以耐受电子中性和贫电子的底物。该反应可耐受多种芳族,杂芳族和非芳族亲核试剂,收率范围为44%至84%。富含对映体的原料产生外消旋产物,表明通过酰基carb离子的S N 1途径。
Reaction of Selenium Dioxide with Aromatic Ketones in the Presence of Boron Triflouride Etherate: A Protocol for the Synthesis of Triarylethanones
An efficient regioselective protocol for the C–C bond formation by the unexpected α,α-diarylation of aromatic ketones with unactivated arenes in the presence of seleniumdioxide and boron trifluoride etherate has been developed. The generality and functional tolerance of this protocol is demonstrated by the synthesis of a series of triarylethanones.