Photochemically driven luminescence switch of metal supramolecular assembly incorporating mixed lanthanides and photochromic guest molecule

We developed a model dual-light-responsive luminescent lanthanide supramolecular switch. A poly[2]pseudorotaxane was firstly constructed from a dilanthanide metal supramolecular assembly (EuTb· 1 EPO ) and an asymmetric diarylperfluorocyclopentene ( 2 ), in which EuTb· 1 EPO exhibits a satisfactory and tunable lanthanide luminescence, while the 2 moiety in the poly[2]pseudorotaxane displays a reversible photochromic process upon light irradiation with an excellent resistance to fatigue. By switching between closed-form and open-form states of 2 using ultraviolet and visible light irradiation alternately, the lanthanide luminescence of poly[2]pseudorotaxane can be quenched and rapidly recovered, that is, the poly[2]pseudorotaxane can be used as switchable controlling unit.