Two new zinc-terephthalate MOFs, (H2NEt2)[Zn3(BDC)3(HCO2)]1.5DEF (1) and Zn4(BDC)3(HCO2)2(DEF)4(2), based on trinuclear zinc secondary building units have been solvothermally synthesized from the well-studied MOF-5 system Zn–H2BDC–DEF (H2BDC = 1,4-benzenedicarboxylic acid or terephthalic acid; DEF = N,N-diethylformamide). It is shown that adding small amounts of formic acid to this system has a great influence on the formation of 3D networks based upon trimetallic zinc building units Zn3(O2CR)6. The structures of 1 and 2 comprise stacked 36 tessellated 2D zinc-terephthalate layers which are linked into 3D frameworks either by bridging formate monoanions (1) or by in situ generated neutral bridging units Zn(HCO2)2(DEF)4 (2). Flowing supercritical-CO2 activation of 1 led to a partially (80%) desolvated and probably collapsed structure (1-SC) with a measured BET (Brunauer–Emmett–Teller) surface area of 38 m2 g-1

Cr-MIL-101-NH ₂ (MOF1) has been used to encapsulate large amounts of copper sulfate and the resulting loaded material, Cu@MOF1, was successfully used to promote the CuAAC click reaction.

Considering the importance of organic functionalization of MOFs, we here report a simple, tunable and efficient one-step post-modification procedure for introducing amino and carboxylic groups into the mesoporous metal–organic framework Al- and Cr-MIL-101-NH₂ based on its reaction with alkyl bromides. This procedure allows also access to polyfunctionalized MIL-101 decorated with both carboxylic and primary amino groups. Other chemical functions, such as alcohols and alkynes, were also successfully introduced by this method.