Photoremovable protecting groups in organic synthesis

Abstract

The applications of light-sensitive protecting groups which can be removed by photolysis in the synthesis of organic compounds are reviewed. The use of groups such as 2-nitrobenzyl, benzyloxycarbonyl, 3-nitrophenyl, phenacyl, 3,5-dimethoxybenzoinyl, and 2, 4-dinitrobenzenesulphenyl for the blocking of various functional groups is reviewed with particular emphasis on their application in syntheses involving polyfunctional molecules. The methods for the incorporation of the protecting group, subsequent synthetic steps, and the final removal of the employed protecting group are illustrated with specific examples. The important applications of these groups in carbohydrate chemistry, nucleotide synthesis, and peptide synthesis on polymeric supports are discussed.