“…In most of the reported reactions, the 3-alkynylated product, i.e., the alkynyl group attached next to the nitrogen atom of the heterocyclic aromatic ring has been obtained exclusively. ,,, In this direction, very recently, some of us reported the first Ru(II)-catalyzed redox-neutral [4 + 2] C–H annulation of N -chlorobenzamides with 1,3-diynes for the synthesis of isoquinolones at room temperature (Scheme ). The reaction exclusively furnished 3-alkynylated isoquinolones for a wide range of substituted N -chlorobenzamides and 1,3-diynes bearing various alkyl substituents. On the contrary, in 2020, Volla and co-workers presented a “reverse” regioselective [4 + 2] annulation of N -hydroxyoximes with 1,3-diynes leading to 4-alkynylated isoquinolines using the [RuCl 2 ( p -cymene)] 2 catalyst…”