Ethynylsulfone‐Based Phenol‐Yne Click Polymerization Toward Multiple Stimulus‐Responsive Poly( β ‐aryloxylvinylsulfone)s

We reported a metal-free ethynylsulfone-based phenol-yne click polymerization for the efficient synthesis of stereoregulated poly(β-aryloxylvinylsulfone)s (PAVSs), a new class of polymers exhibiting inherent responsiveness to multiple stimuli. This polymerization exhibits superior reactivity, yielding high-molecular-weight polymers whose stereochemistry (Z/E configuration) can be precisely modulated by catalysts, monomer concentration, and solvents. The resulting Z- and E-enriched PAVSs demonstrate distinct thermal and mechanical properties, highlighting the impact of stereochemical control on material performance. Furthermore, new stimulus-induced transformations have been developed on the PAVS platform. A catalyst-free amine exchange reaction enables both precise polymer degradation and direct polymer-to-polymer conversion under mild conditions. Moreover, an unprecedented C═C bond cleavage reaction between PAVSs and N,N'-diethylethylenediamine affords methylated products, representing a rare example of alkene bond scission via simple diamine treatment. A photoinduced rearrangement reaction has also been established, leading to significant fluorescence enhancement upon UV irradiation. This photochemical behavior underpins potential applications in secure information encoding and encrypted communication.