Two unique self-penetrating metal–organic frameworks based on flexible tripodal ligands, Cu(II) and N-containing bridging ligands

Solvothermal reaction of Cu(OAc)2·H2O, tri(2-carboxyethyl)isocyanurate (H3tci) and 4,4′-bipyridine (bpy) or 1,3-bis(4-pyridyl)propane (bpp) leads to the generation of two novel metal–organic frameworks, [Cu(Htci)(bpy)]·0.5H2O (1) and [Cu3(tci)2(bpp)2(H2O)]·3H2O (2). 1 features a 3D self-penetrating framework which results from two-fold interpenetrating 4-connected CdSO4 nets linked by carboxylate oxygen atoms of tci ligands. 2 is a 3D self-penetrating 3,4,6-connected 3-nodal net with the stoichiometry (3-c)2(4-c)(6-c) constructed by a two-fold interpenetrating (4.102)2(42.104) net connected by bpp ligands.