NMR measurements were conducted on an AV300nano from Bruker Corporation. Chemical shifts are reported in ppm. H-NMR spectra were referenced to the deuterated solvent as internal standard. Coupling constants (J) are stated in Hertz (Hz). The relative ratio of L1 : L2 contained in MOF samples was determined by digestion and subsequent 1 H-NMR analysis. The digestion of MOF samples was carried out by adding 10 drops of a 98 wt.% D2SO4 solution to 3 mg of sample, and subsequent dilution with 0.8 mL DMSO-d6, followed by 5 min of sonication.