The synthesis of 3-substituted 1-methylpyrrolo[1,2-a]pyrazines and 3-substitutedisoquinolines was achieved by the intramolecular cyclisation of 2-acetyl-1-propargylpyrroles and 2-alkynylbenzaldehydes, respectively, in the presence of ammonia under microwave heating. The tandem imination/annulation of 2-alkynylbenzaldehydes was easily accomplished under standard conditions, while TiCl4 was used to
site-selectivity switch has been achieved in the ruthenium-catalyzed C–H arylation reaction of N-acetyl-1,2-dihydroisoquinolines. This metal-mediated switch is antipodal to the previous report on the palladium-mediated C-4 C–H arylation on the same substrate. Mechanistic details reveal interesting aspects of the reaction pathway, and kinetic studies bring out the difference in the modes of C–H activation
A variety of substituted isoquinoline derivatives can be synthesized in moderate yield by a palladium-catalyzed, microwave-assisted MCR starting from o-bromoarylaldehydes, terminal alkynes, and aqueous ammonia.