Efficient Anti-Markovnikov-Selective Catalysts for Intermolecular Alkyne Hydroamination: Recent Advances and Synthetic Applications

Transition-metal-catalyzed hydroamination of alkynes with primary amines is a reliable tool for the synthesis of imines and enamines. Intramolecular hydroamination has been successfully applied in the synthesis of biologically relevant compounds, but intermolecular hydroamination is less commonly employed in synthesis, due to the possible formation of multiple regioisomers. With catalyst control, regioselectivity can be defined. This microreview focuses on recent advances in intermolecular alkyne hydroamination with primary amines in the presence of transition-metal catalysts that are regioselective for anti-Markovnikov addition. To highlight their potential use in synthesis, some recently developed methodologies that use intermolecular hydroamination in a tandem sequential manner to generate interesting organic cores are also covered.