Synthesis of Pyrimidopyrrolopyridazines via a Tandem Reaction of Heterocyclic Ketene Aminals with 1,2-Diaza-1,3-dienes

Abstract

A tandem reaction of heterocyclic ketene aminals and 1,2-diaza-1,3-dienes was developed for the expedient synthesis of pyrimidopyrrolopyridazine derivatives. This process involved an intramolecular conjugate addition followed by CuCl-catalyzed hydrazone formation.

Direct Access to α-Oxoketene Aminals via Copper-Catalyzed Formal Oxyaminalization of Alkenes under Mild Conditions

“…Ketene aminals constitute an important class of biologically active compounds which are frequently found in many pharmaceuticals and agrochemicals . More importantly, due to their unique structural characteristics, they have been widely used as versatile building blocks for the construction of a range of medicinally relevant heterocyclic compounds in the past years. , In addition, these molecules can serve as efficient ligands in transition-metal catalysis …”

Substrate-Tuned Domino Annulation for Selective Synthesis of Poly-substituted Benzo[f]imidazo[2,1-a][2,7]naphthyridines and 3-Azaheterocyclic Substituted 2-Arylquinolines

“…As such, C3 and N1 of HKAs can serve as bis-nucleophiles to react with bis-electrophiles for the construction of heterocyclic fused compounds . Previously, we and others have discovered the incorporation of two nucleophilic sites N1 and C3 and one electrophile site C4 (CO) through a one-pot cascade reaction to construct polycyclic heterocycles . In continuation of our ongoing efforts to develop one-pot multi-bond forming reactions for the assembly of polycyclic heterocycles, herein we explore the domino annulation of HKAs and 2-aminochalcones through N1, C3, and C4.…”