Phosphine-Promoted C–H Azine Functionalization with Water and Ammonia
Nature reports that simple triarylphosphines enable selective azine C–H coupling with water and ammonia through a non-metal mechanism in which aldehyde/imine motifs interconvert to acetal- and aminal-type forms; this neighboring-group participation guides water and ammonia into a P(V) coordination environment, promoting C–O and C–N bond formation via ligand coupling. The method works across a broad range of pyridines, quinolines, and diazines and provides a late-stage hydroxylation/amination strategy for complex pharmaceuticals and agrochemicals, supported by experimental and computational studies.