Synthesis of α,α-Disubstituted α-Amino Acid Derivatives in Enantiopure Form via Stereoselective Addition of Grignard Reagents to a Chiral Acyclic Nitrone Derived from L-Erythrulose
作者:Raul Portolés、Juan Murga、Eva Falomir、Miguel Carda、Santiago Uriel、J. Alberto Marco
DOI:10.1055/s-2002-25358
日期:——
The additions of various Grignard reagents to a chiral nitrone prepared from L-erythrulose take place with variable diastereoselectivity. The degree and strength of the facial selectivity can be modified if the reaction is performed in the presence of Lewis acidic additives: zinc bromide enhances attack to the si face whereas diethyl aluminum chloride promotes attack to the re side. The obtained adducts