Studies of decarboxylation in photolysis of α-carboxy-2-nitrobenzyl (CNB) caged compounds

Data are shown for photolysis spectra of NPE-caged monomethyl phosphate (Figure S1; page 2) and of 2-nitrobenzyl monomethyl phosphate (Figure S2, page 3). Also shown are isotope effect spectra for photolysis of the two isotopomers of 7 to show the an isotopically-sensitive carboxylate group that disappears on the same time scale as the slow phase of CO2 release (Figure S3, page 4). Details of the synthesis of the precursor compounds for synthesis of 9 are also given (pages 5-6), together with the method used for quantitative measurement of CO2 formation in the IR spectroscopic cells (pages 6-9).