A rare example of SC-SC triggered by Cu2+ heterogeneous oxidation was demonstrated in a Fe(II)-based MOF {[Fe-3(II)(L)(2)(H2O)6].3H(2)O} (1), which occurred a slow conversion into an oxidized MOF 2 ({[Fe-3(II)(L)(2)(H2O)6].3H(2)OOH)}) with retention of single crystallinity. The Fell > Fe' progress of the reaction oxidation was proved by single crystal XRD, PXRD, XPS, s7Fe Mossbauer spectroscopy, and UV vis. We used 1 and 2 as catalysts to catalyze the tandem Nazarov cyclization, and the results show that acylation products were only harvested when 1 was a catalyst, while the oxidized transformer 2 lead mainly to the formation of cyclization products under identical conditions. Through the test of different substrates, 2 can be a good heterogeneous catalyst candidate for the formation of cyclopentenone[b] benzenes. This work provides a new way to design materials.