P-Chiral, N-phosphoryl sulfonamide Brønsted acids with an intramolecular hydrogen bond interaction that modulates organocatalysis.

Brønsted acids exemplified by OttoPhosa I (5c) were designed and evaluated in the asymmetric transfer hydrogenation of quinolines. Their catalytic properties are modulated by an intramolecular hydrogen bond that rigidifies their catalytic cavity, accelerates the reaction rate and improves enantioselectivity.