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.

Thec opper(II)-catalyzed decarboxylative coupling reactions of arylglyoxylic acids with isatins afford 4H-benzo[d][1,3]oxazin-4-ones via decarbonylation and concurrent C-N,C-O bondformation.

A novel ruthenium catalyzed straightforward and efficient synthesis of isocoumarin and α-pyrone derivatives has been accomplished by the decarbonylative addition reaction of anhydrides with alkynes under thermal conditions.