Optical Resolution Membranes from Polysulfones Bearing Alanine Derivatives as Chiral Selectors

Abstract Polysulfones bearing a derivative of alanyl residue employed as chiral selectors were prepared by polymer modification. The specific rotation ([α]_D) of the polysulfone with a derivative of D‐alanyl residue (PSf‐Ac‐D‐Ala) was determined to be 2.87 deg · cm² · g⁻¹ (c = 1.00 g · dL⁻¹ in DMF) and that with L‐alanyl residue (PSf‐Ac‐L‐Ala) to be ‐2.36 deg · cm² · g⁻¹ (c = 1.00 g · dL⁻¹ in DMF). The membrane from PSf‐Ac‐D‐Ala preferentially adsorbed the D‐isomer of Glu from racemic mixture of Glu and vice versa. Chiral separation ability was studied by applying a potential difference as a driving force for membrane transport. The permselectivity of PSf‐Ac‐D‐Ala toward D‐Glu (α_D/L) was determined to be 1.40, and that of PSf‐Ac‐L‐Ala toward the L‐isomer (α_L/D) to be 1.48 at 18.0 V, reflecting their adsorption selectivity. magnified image