Reaction-Based Fluorescent Sensing of Au(I)/Au(III) Species: Mechanistic Implications on Vinylgold Intermediates

A rhodamine-derived alkyne shows turn-on fluorescence change only toward Au(I)/Au(III) species among various other metal species examined. A formyloxazole compound is formed as the major product in aqueous media, presumably via a vinylgold intermediate, which casts new mechanistic implications on vinylgold intermediates.