Sulfoximine-Assisted One-Pot Unsymmetrical Multiple Annulation of Arenes: A Combined Experimental and Computational Study

Discussed herein is an unprecedented Ru-catalyzed one-pot unsymmetrical C-H difunctionalization of arenes comprising intramolecular hydroarylation of olefins and intermolecular annulation of alkynes. This unprecedented 2-fold C-H functionalization is validated on the basis of experimental and density functional theory (DFT) study. The transformation readily occurs with the assistance of methyl-phenyl sulfoximine (MPS) directing group in the presence of Ru catalyst forming two C-C and one C-N bonds in a single operation. The overall process is atom economical and step-efficient and provides unusual dihydrofuran-fused isoquinolone heterocycles. Further annulation of NH and the proximal o-C- H-arene of isoquinolone with alkynes build highly conjugated novel polycyclic compounds. Overall, three independent annulations in arene motifs are visualized and thoughtfully executed; finally, S ring-fused structural entities are constructed forming three C-C and two C-N bonds.