Enantioselective oxidative coupling of methyl 3-hydroxy-2-naphthoate using mono-N-alkylated octahydrobinaphthyl-2,2′-diamine ligand

Mono-N-alkylated octahydrobinaphthyl-2,2′-diamine (H₈-BINAM) chiral ligands were employed in the catalytic and asymmetric oxidative coupling of methyl 3-hydroxy-2-naphthoate to the corresponding binaphthol derivative. The diamine ligand with one N-(3-pentyl) group shows highest enantioselectivity in the biaryl coupling among other BINAM derivatives, and the coupling reaction proceeds faster than the reactions using alkanediamine ligands.