Ru3(CO)12-catalyzed C-H/CO/olefin coupling of N-pyridylindolines.: Direct carbonylation at a C-H bond δ to the pyridine nitrogen

The reaction of N-pyridylindolines with CO and ethylene in the presence of Ru-3(CO)(12) results in direct carbonylation at a C-H bond delta to the pyridine sp(2) nitrogen, which represents a new type of C-H/CO/olefin coupling. The presence of a pyridine ring as a directing group on the substrates is essential for the reaction to proceed. The choice of N,N-dimethylacetamide (DMA) as the solvent is crucial for the reaction to proceed efficiently.