A new and efficient aerobic oxidation of aldehydes to carboxylic acids with singlet oxygen in the presence of porphyrin sensitizers and visible light

A new aerobic route is introduced for the oxidation of a variety of aromatic and aliphatic aldehydes to the corresponding carboxylic acid derivatives using molecular oxygen in the presence of tetraphenylporphyrin (H2TPP), tetramesitylporphyrin (H2TMP), tetrakisdichlorophenylporphyrin (H2TDCPP), ZnTPP, and ZnTMP as sensitizers using visible light in an organic solvent. The method has a wide range of applications, does not involve cumbersome work-up, exhibits chemoselectivity, and proceeds under mild reaction conditions. The products are obtained with good conversions and in reasonable reaction times.