Carboxylation of benzylic and aliphatic C-H bonds with CO2 induced by light/ketone/nickel
A photoinduced carboxylation reaction of benzylic and aliphatic C-H bonds with CO2 is developed. Toluene derivatives capture gaseous CO2 at the benzylic position to produce phenylacetic acid derivatives when irradiated with UV light in the presence of an aromatic ketone, a nickel complex, and potassium tert-butoxide. Cyclohexane reacts with CO2 to furnish cyclohexanecar-boxylic acid under analogous reaction conditions. The present photoinduced carboxylation reaction provides a direct access from readily available hydrocarbons to the corresponding carboxylic acids with one carbon extension.
Synthesis of 4-Hydroxy-2-methylbenzoic Acid and Its Higher Homologues
Synthesis of 4-hydroxy-2-methylbenzoic acid (1a) and its higher homologues such as 4-hydroxy-2-methylphenylacetic acid (1b), 3-(4-hydroxy-2-methylphenyl)propanoic acid (1c) and 4-(4-hydroxy-2-methylphenyl)butanoic acid (1d) are described.
Sen, P. K.,Pal, Panchanan,Goswami, Shyamaprosad,Chattopadhyay, Gautam