Organic–inorganic hybrid supermicroporous chromium oxophenylphosphate with magnetic and catalytic properties

Abstract Organic–inorganic hybrid chromium oxophenylphosphate CPP-1 has been synthesized hydrothermally in the presence of phenylphosphonic acid as a phosphorus source without the aid of any structure directing agent (SDA). The material has high BET specific surface area of 315 m 2 g −1 and consists of large supermicropores of dimension ca . 1.4 nm. Powder XRD analysis revealed the crystalline feature and a new orthorhombic phase for CPP-1 with unit cell parameters of a =14.8232 A, b =6.87167 A, c =18.2501 A, α=β=γ =90°. Magnetic measurements suggested that in CPP-1 the metal centers are bridged via the phenylphosphate group and they are antiferromagnetically coupled. The coupling strength is relatively weak (−2.33 cm −1 ) in this porous network and much lower than the conventional M–O–M superexchange interaction. CPP-1 also showed good catalytic activity in the liquid phase partial oxidation of aldehydes to the respective acids in the presence of dilute aqueous H 2 O 2 as oxidant at room temperature.