Synthesis of carboxylic acids by hydrolysis or saponification
N,N-diarylammonium pyrosulfate efficiently catalyzes the hydrolysis of esters under organic solvent-free conditions. This reverse micelle-type method is successfully applied to the hydrolysis of various esters without the decomposition of base-sensitive moieties and without any loss of optical purity for α-heterosubstituted carboxylic acids.
Y. Koshikari, A. Sakakura, K. Ishihara, Org. Lett., 2012, 14, 3194-3197.
A highly efficient semi-two-phase reaction using THF-aqueous NaOH at 0°C provides half-esters from symmetric diesters in high yields. Diesters that afforded the corresponding half-esters in quantitative yields all possess two carboalkoxy groups in "cis" or "geminal" orientation.
S. Niwayama, J. Org. Chem., 2000, 65, 5834-5836.
Aluminum powder and iodine in anhydrous acetonitrile mediate a one-pot deprotecting of alkyl carboxylates under nonhydrolytic conditions. Cleavage of lactones affords the corresponding ω-iodoalkylcarboxylic acids. This method enables the selective cleavage of alkyl carboxylic esters in the presence of aryl esters.
D. Sang, H. Yue, Y. Fu, J. Tian, J. Org. Chem., 2021, 86, 4254-4261.