Ru(II)-Catalyzed C–H Activation and Annulation Reaction via Carbon–Carbon Triple Bond Cleavage

An unprecedented Ru­(II)-catalyzed C–H activation and annulation reaction, which proceeds via C–C triple bond cleavage, is reported. This reaction of 2-phenyl­dihydro­phthalazine­diones with alkynes, which works most efficiently in the presence of bidented ligand 1,3-bis­(diphenylphosphino)­propane, affords good yields of substituted quinazolines