Ultraviolet-responsive self-assembled metallomicelles for photocontrollable catalysis of asymmetric sulfoxidation in water

Abstract

Self-assembled metallomicelles with ultraviolet (UV)-controlled morphologies were constructed from a synthesized azobenzene-containing amphiphilic chiral salen Ti^IV catalyst. The morphologies of the metallomicelles could be well adjusted by changing the UV irradiation time, and this was confirmed by TEM analyses. The UV-induced change in morphology potentially adjusted the catalyst concentration and/or accessibility in real-time, allowing photocontrollable catalysis of asymmetric sulfoxidation in water. UV-responsive catalytic activities with excellent selectivities were observed over the metallomicelles for a wide range of alkyl aryl sulfides. Moreover, a thermo-responsive NIPAAm block in the catalyst enables it to be easily recovered for steady reuse by thermo-controlled separation. This work constructed a photo-responsive metallomicellar system to carry out metallomicellar catalysis in a controllable way.