Carbamates relative cleavage rates

Disubstituted-6-nitrobenzyl Carbamates. A series of different 3,4-disubstituted 6-nitrobenzyl carbamates were prepared and their cleavage rates examined at 254 nm and 420 nm. These studies showed that the 3-chloro or 3-bromo derivatives cleave faster at 254 nm than does the 2-nitroveratrole-derived carbamates whereas at 420nm the relative rates are reversed."... 

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