engleski

Activation of C–H Bond in Benzo[h]quinoline with Various PdII Precursors

Activation of unreactive C–H bonds with PdII precursors is the most common method for the preparation of organopalladium compounds, known as palladacycles, and it is the key step in many catalytic reactions induced by palladium catalysts. These processes mainly rely on solvent-based protocols, which may require toxic solvents and are often long lasting. Recent advances in performing chemical transformations under milling conditions resulted in the first mechanosynthesis of palladacycles via C–H bond(s) activation. This synthesis promptly led to the use of ball milling methods in the metal-catalyzed functionalization of organic molecules, followed by the first comparative mechanistic study on the regioselective mechanochemical C–H bond activation in an unsymmetrical azobenzene substrate by the most common PdII catalysts, using liquid and/or solid additives. Within this work, the reactivity trend found for the PdII catalytic precursors in above-described reactions ([Pd(OAc)2]3 < PdCl2 < [Pd(MeCN)4[BF4]2) was tested in their reactions with benzo[h]quinoline which contains only one C–H bond for directed C–H activation in contrast to the 4, 4’-substituted azobenzenes (Scheme 1).

C-H bond activation ; benzo[h]quinoline ; palladium ; mechanochemistry

nije evidentirano