Rh(III)-catalyzed chelation-assisted C–H activation/annulation of 2-arylimidazolines with cyclic diazo-1,3-dicarbonyl compounds: a novel approach to tetracyclic annulated derivatives of 2,3-dihydroimidazo[2,1-a]isoquinoline

• Ivan Lyutin,
• Grigory Kantin,
• Olga Bakulina and
• Dmitry Dar'in

Beilstein J. Org. Chem. 2026, 22, 997–1003, doi:10.3762/bjoc.22.78

• )-catalysis for the first time. The developed general and efficient approach based on CH-activation allowed the efficient preparation of five novel types of tetraheterocyclic systems derived from 2,3-dihydroimidazo[2,1-a]isoquinolines fused with an additional five-, six- or seven-membered carbocycle or N-/O

• -heterocycle. Keywords: annulation; 2-arylimidazolines; catalysis; С–H activation; diazodiketones; 2,3-dihydroimidazo[2,1-a]isoquinolines; dimedone; tetraheterocycles; Introduction The advancement of organic synthesis techniques, especially methods for creating nitrogen-containing heterocycles, is essential

• synthesizing imidazolines [7][8], but access to their annulated derivatives is still very limited despite many promising results on their bioactivity. For example, several derivatives of 5-aryl-2,3-dihydroimidazo[2,1-a]isoquinolines (Figure 1, 1) have demonstrated antitumor [9][10][11], anti-inflammatory, and