Fluorogenic Transformations Based on Formation of CC Bonds Catalyzed by Palladium: An Efficient Approach for High Throughput Optimizations and Kinetic Studies

We have developed novel fluorogenic transformations based on formation of CC bonds catalyzed by palladium using iodocoumarin 1 as a model aryl iodide, where fluorescence is quenched completely due to effects of the heavy, polarizable iodine atom. Substitution of the iodine atom for the carbon using Sonogashira, Suzuki-Miyaura and Heck couplings results in a dramatic fluorescence en- hancement. This approach has been used successfully for the optimization of reaction conditions and kinet- ic studies in high throughput format.