Advances in the Synthesis of Isoquinolines Using an Alkyne Coupling Partner via Transition‐Metal‐Catalyzed C─H Activation

Abstract Isoquinoline is a privileged structural motif and has extensive applications in asymmetric catalysis, photochemistry, and pharmaceutical use. Naturally, isoquinoline is a popular synthetic target for many research groups worldwide, who, as a result, have developed numerous methodologies to afford a wide variety of derivatives. The synthesis of isoquinoline in recent years has flourished, employing C─H activation strategies using various transition metal catalysts: rhodium (Rh), ruthenium (Ru), nickel (Ni), manganese (Mn), and cobalt (Co). To summarize this diverse area of study, this review comprehensively assimilates the literature where isoquinolines are synthesized using alkynes (both internal and terminal) as coupling partners. Wherever possible, the mechanistic details associated with the reported reactions are provided.