A rapid injection NMR study of the chelation controlled Mukaiyama aldol addition: TiCl4 versus LiClO4 as the Lewis acid
作者:Manfred T Reetz、Burkhard Raguse、Charles F Marth、Helmut M Hügel、Thorsten Bach、David N.A Fox
DOI:10.1016/0040-4020(92)80024-a
日期:1992.7
The concept of chelationcontrolled addition to chiral alkoxy aldehydes using Lewisacids and mild C-nucleophiles has been extended to include cyclopropylation. The mechanism of the TiCl4-mediated chelationcontrolled addition of enolsilanes and allylsilanes to chiral α-alkoxy aldehydes has been studied by rapid injection NMR techniques. Accordingly, an acyclic transition state is involved in which