Synthesis of Enantiopure Functionalized Pipecolic Acids via Amino Acid DerivedN-Acyliminium Ions
作者:Floris P. J. T. Rutjes、Johan J. N. Veerman、Wim J. N. Meester、Henk Hiemstra、Hans E. Schoemaker
DOI:10.1002/(sici)1099-0690(199905)1999:5<1127::aid-ejoc1127>3.0.co;2-a
日期:1999.5
The synthesis and enzymatic resolution of a novel vinylsilane-containing amino acid is described. Derivatization of this and other olefinic amino acids followed by subjection to standard N-acyliminium ion cyclization conditions provides the corresponding pipecolic acid derivatives with - in most cases - complete conservation of enantiopurity. In addition to studying the scope of this reaction, details of the N-acyliminium ion cyclization including an aza Cope equilibrium are highlighted.