Synthesis and Mechanistic Study of Cyclic Oxoguanidines via Zn(OTf)2 -Catalyzed Guanylation/Amidation from Readily Available Amino Acid Esters and Carbodiimides

Chemistry. 2015 Jul 13;21(29):10369-78. doi: 10.1002/chem.201500573. Epub 2015 May 26.

Abstract

The Zn(OTf)2 -catalyzed guanylation/amidation from readily available amino acid esters and carbodiimides is achieved to provide efficiently various cyclic oxoguanidines, including 2-amino-1H-imidazol-5(4H)-ones and 2-aminoquinazolin-4(3H)-ones in medium-to-high yields. It is the first time that an ammonium salt has been used in a guanylation reaction. The application of cyclic oxoguanidines to provide the conjugated heterocyclic compounds via oxidative C-N formation or aldol reaction is explored. The reaction mechanism is well elucidated by the isolation and characterization of three important intermediates.

Keywords: amino acid esters; carbodiimides; cyclic oxoguanidines; cyclization; guanylation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acids / chemistry*
  • Aminoquinolines / chemistry*
  • Carbodiimides / chemistry*
  • Catalysis
  • Esters
  • Guanidines / chemical synthesis*
  • Guanidines / chemistry
  • Heterocyclic Compounds / chemical synthesis*
  • Heterocyclic Compounds / chemistry
  • Imidazoles / chemistry*
  • Mesylates / chemistry*
  • Molecular Structure
  • Stereoisomerism

Substances

  • Amino Acids
  • Aminoquinolines
  • Carbodiimides
  • Esters
  • Guanidines
  • Heterocyclic Compounds
  • Imidazoles
  • Mesylates
  • imidazolone
  • trifluoromethanesulfonic acid