Postsynthetic Rearrangement/Metalation as a Route to Bimetallic Uranyl Coordination Polymers: Syntheses, Structures, and Luminescence

Abstract

Postsynthetic metalation of a uranyl isonicotinate starting material (UICP) with Ag(I) and Cu(II) under hydrothermal conditions has yielded two new coordination polymers: (UO2)(OH)(C6H4NO2)2Ag (1) and (UO2)2(O)(OH)(C6H4NO2)2Cu(OH2)Cl (2). The Ag(I) in 1 directly replaces a proton in UICP and thus generates a similar topology. Compound 2, however, is formed by a topological rearrangement of the starting material upon metalation. Comparison of postsynthetic metalation and direct assembly reveals that compound 1 may be synthesized via both methods, whereas 2 was only be prepared by the former. Attempts to prepare 2 via direct assembly yielded (UO2)(OH2)2(C6H4NO2)2Cu2(C6H4NO2)4(OH2)2 (3). Use of postsynthetic metalation has proven to be a route to bimetallic uranyl-bearing coordination polymers and may yield materials otherwise inaccessible via direct assembly.