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

Highlight
• Organic–inorganic hybrid chromium oxophenylphosphate CPP-1.
• CPP-1 showed high surface area and supermicroporosity.
• Cr centers are bridged via the phenylphosphate group and they are antiferromagnetically coupled.
• Powder XRD revealed a new orthorhombic phase for CPP-1.

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 m2 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 Å, b=6.87167 Å, c=18.2501 Å, 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 H2O2 as oxidant at room temperature.

Porous chromium oxophenylphosphate have been synthesized hydrothermally by using phenylphosphonic acid as P source. The material showed supermicroporosity, antiferromagnetically coupled binuclear structure and catalytic property in the liquid phase oxidation reactions.Figure optionsDownload as PowerPoint slide