Wavelength-selective cleavage of photolabile protecting groups

The selective photocleavage of protecting groups using monochromatic light is described. Some groups were found to react faster than others at 254 nm, whereas this trend was reversed at 419 nm. This behavior was preserved in solution mixtures of both groups. The selective control of which group is activated is thus achieved by using an influence external to the reaction mixture. (C) 2000 Elsevier Science Ltd. All rights reserved.