Tandem Protocol for the Stereoselective Synthesis of Different Polyfunctional β-Amino Acids and 3-Amino-Substituted Carbohydrates
作者:Norbert Sewald、Klaus D. Hiller、Matthias Körner、Matthias Findeisen
DOI:10.1021/jo980656z
日期:1998.10.1
Conjugateaddition of homochiral amidocuprates or lithium amides based on (R)-N-(1-phenylethyl)(trimethylsilyl)amine to alpha,beta-unsaturated esters proceeds stereoselectively and allows the synthesis of beta-amino acids. Trapping of the intermediate ester enolate with D(2)O affords the corresponding deuterated compounds. anti-alpha-Alkyl-beta-amino acids are obtained stereoselectively after transmetalation
A synthesis of aziridine esters based on the cyclisation of amino selanyl esters induced by the selanyl group activation was developed with either the Meerwein salt or NBS. Twoasymmetricapproaches are proposed: the diastereoselective reductions of α-selanyl β-iminoesters derived from α-oxoesters, which lead to cis chiral aziridine esters 6 and 6′; and the diastereoselective conjugate additions of