Ruthenium-Catalyzed Carbonylation of Oxalyl Amide-Protected Benzylamines with Isocyanate as the Carbonyl Source

An efficient synthesis of isoindolin-1-ones from oxalyl amide-protected benzylamines, through ruthenium-catalyzed intramolecular C­(sp2)-H carbonylation, has been developed. Variously substituted benzylamines could be well tolerated in this new protocol, affording the corresponding products in moderate to excellent yields. This approach constitutes the first example of Ru­(II)-catalyzed C­(sp2)-H carbonylation with isocyanate as a novel commercially available carbonyl source.