Three novel 3D (3,8)-connected metal-organic frameworks constructed from flexible-rigid mixed ligands

Three novel 3D (3,8)-connected networks, namely [Cd-2(L1)(2)(1,3-bdc)] 1, [Cd-2(L2)(2)(1,4-bdc)] center dot 3H(2)O 2 and [Cd-3(L3)(2)(1,3-bdc)(2)] 3, where L1 = 3,5-bis(pyridin-4-ylmethoxy)benzoic acid, L2 = 3,4-bis(pyridin-4-ylmethoxy)benzoic acid, L3 = 3,5-bis(pyridin-3-ylmethoxy)benzoic acid, bdc = benzenedicarboxylate, have been synthesized hydrothermally and characterized. Complex 1 exhibits a twofold interpenetrating network constructed from Cd-2-based secondary building units (SBUs) [Cd-2(CO2)(2)O2N4] with (4(2).6)(2)(4(4).6(22).8(2)) topology. Complex 2 is constructed from Cd-2-based SBUs [Cd-2(CO2)(4)N-4] with (4(3))(2)(4(6).6(18).8(4)) topology. The structure of 3 is based on linear Cd-3-based SBUs [Cd-3(CO2)(6)N-2] with a Schlafli symbol (4(2).5)(2)(4(4).5(6).6(10).7(5).8(2).9). In addition, X-ray powder diffraction (XRPD) and luminescent properties of 1-3 were also investigated in detail.