Meichao Li

A practical iodine-catalyzed oxidative conversion of aldehydes to nitriles

A simple and efficient method for the direct synthesis of nitriles from aldehydes using ammonium acetate as the nitrogen source has been developed. The reactions were performed with iodine as the catalyst and tert-butyl hydroperoxide (TBHP) as the oxidant under mild conditions. A variety of aromatic, heteroaromatic, aliphatic and allylic aldehydes could be converted into their corresponding nitriles in good to excellent yields.

Selective oxidation of benzyl alcohol on poly(4-(3-(pyrrol-1-yl)propionamido)-2,2,6,6-tetramethylpiperidin-1-yloxy) electrode

The derivative monomer of pyrrole with the side chain nitroxyl radical, 4-(3-(pyrrol-1-yl)propionamido)-2,2,6,6-tetramethylpiperidin-1-yloxy (PyATEMPO) was synthesized. Its corresponding polymer PPyATEMPO was successfully prepared by cyclic voltammetry on Pt electrode in NaClO4/CH3CN solution. The PPyATEMPO electrode showed high electrocatalytic activity for oxidation of benzyl alcohol in the presence of the Lewis base 2,6-lutidine. To further investigation, in situ Fourier transform infrared (FTIR) spectroscopy technique was applied to study the possible electrochemical oxidation mechanism of benzyl alcohol on PPyATEMPO electrode. It showed that the benzyl alcohol was selectively oxidized to benzaldehyde in the action of PPyATEMPO film.

2,3-Dichloro-5,6-dicyano-1,4-benzoquinone-catalyzed aerobic oxidation reactions via multistep electron transfers with iron(II) phthalocyanine as an electron-transfer mediator

A new biomimetic catalytic oxidation system which employs 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) as the catalyst, molecular oxygen as the terminal oxidant and iron(II) phthalocyanine (FeIIPc) as the electron-transfer mediator has been developed. This system can be applied for oxidative deprotection of PMB ethers, alcohol oxidation, aromatization and α,β-unsaturated aldehyde formation. After immobilizing FeIIPc on multi-walled carbon nanotubes, it can be reused without loss of activity.