Formation of 1,1 ′-iminodicarboxylic acid derivatives, 2,6-diketo-piperazine and dibenzodiazocine-2,6-dione by variations of multicomponent reactions

The combination of multicomponent reactions (MCRs) of different amino acids, aldehydes, isocyanides and acids allows complex structures to be prepared in one-pot reactions. The synthesis of 1,1 ′-iminodicarboxylic acid derivatives 12 demonstrates the high selectivity of the Ugi Four Component Reaction using two different aldehydes and two different isocyanides. The limitations of the MCRs are illustrated by the synthesis of a 1,1 ′-iminodicarboxylic acid derivative 6 from l-lysine. Furthermore, 2,6-diketopiperazines and dibenzodiazocin-2,6-diones are synthesized via MCRs.