“…Structural variations of the ligand include alteration of P -substitution and modifications of the phenyl backbone, including the synthesis of supramolecular chiral ligands appended with crown ethers that induce strong complexation between the ligand and alkali cations . Since 2011, the combination of iridium and biaryl bisphosphine ligands has been extensively studied by Zhou, Agbossou-Niedercorn, and Mashima in the asymmetric hydrogenation of heteroarenes, including quinolines, isoquinolines, , quinoxalines, , pyridines, pyrazines, and benzoxazines . Iodine, chloroformates, amines, and Brønsted acids are common activating reagents for enhancing catalytic activity of these heterocyclic substrates.…”