Molecular mechanism of uncaging CO2 from nitrophenylacetate provides general guidelines for improved ortho-nitrobenzyl cages.

Femtosecond spectroscopy and quantum chemical calculations provide detailed insights into the specificities of the uncaging mechanism of CO2 from ortho-, meta-, and para-nitrophenylacetate. The emerging general principles allow a rational design of improved ortho-nitrophenyl cages for chemical and biological applications.