Ruthenium-Catalyzed N-Alkylation for the Synthesis of 2-N-Pyridylmethyl Benzonitriles and an Exploration of Its Synthetic Utility

The N-alkylation of 2-aminobenzonitriles with pyridyl methanols as the alkylating reagents has been demonstrated by using an easily available Ru-3(CO)(12)/Binap/tBuOK [Binap=2,2-bis(diphenylphosphino)-1,1-binaphthyl] catalyst system. The synthetic protocol can be used to synthesize various 2-N-pyridylmethyl benzonitriles in moderate to good isolated yields. Through an exploration of its synthetic utility, we have demonstrated a novel straightforward synthesis of biologically interesting 2,3-diaryl-1,2,3,4-tetrahydrobenzo[e][1,4]diazepin-5-ones, which provides an important basis for the discovery of new bioactive compounds.