Efficient synthesis and facile functionalization of highly fluorescent spiro [pyrrol-pyran]

Decent fluorescent scaffolds with desirable property and extensibility play critical role in the development of fluorescent material science and chemical biology. This contribution describes an efficient multicomponent strategy to construct spirocyclic scaffold SPP (spiro[pyrrol-pyran]) with differing substituents under mild condition. Through one-pot reaction, arylacetylene decorated by varying electron donating group can efficiently react with tetracyanoethylene, and alcohol or primary amine, producing a series of color tunable fluorophores with large stokes shift (up to 190 nm) and high fluorescent quantum yield (up to 0.83). The SPP core shows good structural stability towards pH and optical radiation. The polymeric spiro derivative NO6 was further functionalized to construct energy-transfer probe for ratiometric sensing ONOO-.