Tuning Structural Topologies of a Series of Metal–Organic Frameworks: Different Bent Dicarboxylates

Five
new metal–organic frameworks incorporating the angular
tetratopic ligand with different transition metal ions and bent coligands
have been synthesized: [Zn4(L)2(4,4′-sdb)4(H2O)2]·3H2O (1), [Zn2(L)2(hfipbb)2(H2O)3] (2), [Zn­(L)­(oba)]·H2O (3), [Cd2(L)2(4,4′-sdb)2]·2H2O (4), [Cd2(L)­(hfipbb)­(H2O)3]·2H2O (5), [L
= 1,1′-oxybis­[3,5-dipyridine-benzene, 4,4′-H2sdb = 4,4′-sulfonyldibenzoate, H2hfipbb = 4,4′-(hexafluoroisopropylidene)­bis­(benzoic
acid), H2oba = 4,4′-oxybis­(benzoate)]. Structural
analysis reveals that the mixed ligands display versatile coordination
modes to manage the metal ions to form homochiral, inclined polycatenation
(1D → 2D), 3-fold interpenetrating nets. However, the different
coordinated modes, geometry, and flexibility of ligands around metal
ions result in subtle differences in the final architecture. Bulk
materials for 1 and 3 have a second-harmonic
generation activity, approximately 0.4 and 0.8 times that of urea.