Two new bismuth metal-organic frameworks (Bi-MOFs) were discovered using high throughput experiments employing bismuth(iii) nitrate pentahydrate and triazine-2,4,6-triyl-tribenzoic acid (HTATB). The reaction was carried out for long reaction times (∼5 d) in a water/DMF-mixture and resulted in the formation of [Bi(O)(OH)(TATB)]·HO (denoted as CAU-35). By switching to short reaction times and a methanol/DMF-mixture as the solvent, an analogue of CAU-7-BTB with the composition [Bi(TATB)]·DMF·6HO (denoted as CAU-7-TATB) was obtained. The use of the amino-functionalised HTATB linker (HTATB-NH) resulted in the formation of a functionalised porous Bi-MOF with the composition [Bi(TATB-NH)]·5HO·0.5DMF (CAU-7-TATB-NH). The structures of CAU-35 and CAU-7-TATB were successfully solved and refined from the PXRD data. CAU-7-TATB-NH was post-synthetically modified using anhydrides (acetic anhydride and valeric anhydride), cyclic anhydrides (succinic anhydride and phthalic anhydride), and 1,3-propane sultone. The degree of conversion ranged from 33% to 79%.

Ten benzene based linkers containing sulfonic and phosphonic acids have been synthesized. One lanthanum MOF was isolated and characterized.

New triazine-based tricarboxylic acid linkers were prepared as elongated relatives of triazinetribenzoic acid (TATB). Additionally, functional groups (NO2, NH2, OMe, OH) were introduced for potential post-synthetic modification (PSM) of MOFs. Functionalized tris(4-bromoaryl)triazine “cores” (3a,3b) were obtained by unsymmetric trimerization mixing one equivalent of an acid chloride (OMe or NO2 substituted) with two equivalents of an unsubstituted nitrile. Triple Suzuki coupling of the cores 3 with suitable phenyl- and biphenylboronic acid derivatives provided elongated tricarboxylic acid linkers as carboxylic acids 17 and 20 or their esters 16 and 19. Reduction of the nitro group and cleavage of the methoxy group gave the respective amino and hydroxy-substituted triazine linkers.

Several mesoporous iron(iii)-based mixed linker MOFs were synthesized; all exhibiting MIL-143 topology. This structure type is tolerant to variation in the functional groups (e.g. nitro and/or amino) along the linkers.

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