Uranyl ion complexes with 2,2′:6′,2′′-terpyridine-4′-carboxylate. Interpenetration of networks involving “expanded ligands”

Pierre Thuéry (1) , Jack Harrowfield (2)

1 LCMCE - Laboratoire de Chimie Moléculaire et de Catalyse pour l'Energie (ex LCCEF)
2 ISIS - Institut de Science et d'ingénierie supramoléculaires

2,2':6',2"-Terpyridine-4'-carboxylic acid (tpycH) has been used as a ligand in the synthesis of four uranyl ion complexes under solvo-hydrothermal conditions. The homometallic complex [(UO2)2(tpyc)(HCOO)(OH)2] (1) contains additional hydroxide and formate anions generated in situ and it crystallizes as a monoperiodic coordination polymer in which uranyl cations are bound to both the carboxylate group and the terpyridine N3 site. Addition of PbII gives the heterometallic complex [UO2Pb(tpyc)(HCOO)2(OH)(H2O)2] (2), in which uranyl is bound to the carboxylate group while lead(II) occupies the N3 site, further hydroxide- and formate-bridging resulting in a diperiodic arrangement. Both complexes [UO2Ni(tpyc)2(OH)(H2O)].NO3.1.5H2O (3) and [(UO2)2Ni2(tpyc)4(O)(H2O)4].(NO3)2.6H2O (4) contain the neutral, octahedral Ni(tpyc)2 “expanded ligand” unit, the uranyl cations being bound to the divergent carboxylate groups and to bridging hydroxo or oxo groups. Complex 3 crystallizes as a heavily corrugated diperiodic assembly in which hydroxo-bridged dinuclear secondary building units are the nodes of a network of sql topology. Diperiodic polymers with the same topology but a different shape are formed in 4, which are involved in twofold parallel interpenetration

Domaines: Cristallographie

Pierre Thuéry, Jack Harrowfield. Uranyl ion complexes with 2,2′:6′,2′′-terpyridine-4′-carboxylate. Interpenetration of networks involving “expanded ligands”. CrystEngComm, In press, 23, pp.7305-7313. ⟨10.1039/D1CE01215K⟩. ⟨cea-03364878⟩