Synthesis and derivatization of N-amino amidrazones via coupling of aldehyde hydrazones with dialkyl azodicarboxylates

Abstract

We herein report a concise and convenient protocol for the synthesis of N-amino amidrazones via the coupling of aldehyde-derived hydrazones with dialkyl azodicarboxylates. This method provides efficient access to a diverse range of N-amino amidrazones in excellent yields. Furthermore, we demonstrate that these intermediates can be efficiently transformed into synthetically valuable tetrahydrotetrazine scaffolds through a one-pot procedure. Mechanistic studies reveal that the transformation proceeds via two distinct pathways: an initial polar, electrophilic addition to form the N-amino amidrazone core, followed by a photoinduced oxidative cyclization to construct the tetrahydrotetrazine skeleton.