Ru(II)-Catalyzed\nRedox-Neutral C–H Olefination\nand Tandem Cyclization with Vinyl Sulfones: Leveraging Sulfinate Anion\nas a Leaving Group for the Synthesis of 3‑Methyleneisoindolin-1-ones

We developed a Ru(II)-catalyzed redox-neutral C–H\nolefination\nof <i>N</i>-methoxybenzamides with vinyl sulfones. The reaction\nis operationally simple and conducted at ambient temperature and does\nnot require silver additives or external oxidants, making it suitable\nfor late-stage functionalization. Notably, we leveraged the leaving\ngroup ability of sulfinate anion to synthesize 3-methyleneisoindolin-1-ones\nthrough a tandem C–H olefination/cyclization/elimination sequence\nat ambient temperature. Moreover, we successfully demonstrated the\nsynthetic versatility of 3-methyleneisoindolin-1-one for the construction\nof an isoindolobenzazepine core.