Synthesis of Nβ-Substituted 1,2-Diazetidin-3-ones by the Ugi Reaction Comprising Chiral α-Hydrazino Acids.

We report the synthesis of a structurally diverse library of chiral Nβ-substituted 1,2-diazetidin-3-ones by a 4-center 3-component Ugi reaction comprising unprotected α-hydrazino acids. Various isocyanides and carbonyl compounds and both aldehydes and ketones were utilized. In addition, postcondensation modifications at three different sites have been demonstrated.