Novel fluorescent coumarin reagents appending 15-crown-5 ether for the rapid and self-catalytic derivatization of carboxylic acids

Novel fluorogenic coumarin derivatives appending 15-crown-5 ether as more a ctive catalytic site were designed and synthesized for the fluorescence der ivatization of carboxylic acids. From the stability constants (K-s) for com plexation with metal acetates in methanol, it was found that their catalyti c abilities were superior to the corresponding benzo-15-crown-5 ether type reagent. However, the reactivity of these reagents in the derivatization of lauric acid was dependent on not only the catalytic ability of the introdu ced crown-ether but also on the appending position of that in a reagent mol ecule. Furthermore, the derivatized products showed remarkably high fluores cence quantum yields of above 0.8 in methanol and acetonitrile. Allowing to hold a certain function such as catalyst in a reagent molecule should serv e as a new strategy for the development of excellent analytical reagents.