6-Alkynyl- and 6-Aryl-Substituted (R)-Pipecolic Acid Derivatives
摘要:
(R)-alpha-Aminoadipic acid is a readily available enantiomerically pure starting material for the synthesis of (R)-pipecolic acid and its derivatives. Sonogashira or Suzuki cross-coupling reactions of an Wormyl pipecolate-derived vinyl bromide furnish 6-alkynyl or aryl derivatives. Reduction with sodium cyanoborohydride and subsequent N-deformylation provide 6-alkynyl substituted (R)-pipecolic acid derivatives, valuable building blocks for amino acid and peptide chemistry.