Solvothermal reaction of H2btdd with Mn(OAc)2 (OAc = CH3CO2) in DMF/CH3OH (9:1 v/v) or CdI2 in DMF yielded microcrystalline powders of the cubic MFU-4l-type framework, which we respectively name Mn(OAc)-MFU-4l and CdI-MFU-4l. Empirically, we found that the choice of metal salt and reaction conditions are critical to obtain the MFU-4l phase exclusively, avoiding the formation of the hexagonal M2X2(btdd) phase and other phases. Powder x-ray diffraction patterns of activated Mn(OAc)-MFU-4l and CdI-MFU-4l are nearly identical to that of ZnCl-MFU-4l, indicating the structural similarity of these frameworks (Figure ). As metal ionic radius increases from Zn II to Mn II to Cd II , the peak positions shift to lower angles such that the unit cell parameter a increases along the series ZnCl-MFU-4l < Mn(OAc)-MFU-4l < CdI-MFU-4l. For example, the most intense peak, corresponding to the (200) plane, is observed with Cu Kα at 2θ = 5.70, 5.64, and 5.58° for ZnCl-MFU-4l, Mn(OAc)-MFU-4l, and CdI-MFU-4l, respectively, at room temperature. The robustness of the crystal structures after activation is also supported by N2 adsorption data collected at 77 K. The materials show steep N2 uptake below P/P0 = 0.1, reaching capacities of more than 25 mmol/g and demonstrating the presence of permanent porosity. From these data, the Brunauer-Emmett-Teller (BET) surface areas are estimated to be 3180(20) m 2 /g for Mn(OAc)-MFU-4l and 2480 (20) for CdI-MFU-4l (Table ).