Ruthenium(II)‐Catalyzed CH Activation with Isocyanates: A Versatile Route to Phthalimides

Abstract A cationic ruthenium(II)‐complex was utilized in the efficient synthesis of phthalimide derivatives by CH activation with synthetically useful amides. The reaction proceeded through a mechanistically unique insertion of a cycloruthenated species into a CHet multiple bond of isocyanate. The novel method also proved applicable for the synthesis of heteroaromatic unsymmetric diamides as well as a potent COX‐2 enzyme inhibitor.