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Herein, we report the coordination-driven self-assembly of a diazaporphyrin plate and a porphyrin prism, made using the same Ru-benzo molecular clip and 2:1 diruthenium acceptor to tetrapyridyl donor stoichiometry, and discuss characterization techniques used to distinguish the two. We describe how 1H NMR data can distinguish between plate and prism geometries based on peak shifts and splitting in the context of molecular symmetries. DOSY spectra show changes in hydrodynamic radius from the monomeric porphyrin to the prism (4.78 Å to 15.2 Å) and diazaporphyrin to plate (6.02 Å to 12.2 Å) consistent with the increase in size upon assembly. High resolution mass spectrometry provides further evidence for plate and prism, where specific peaks at diagnostic m/z values unequivocally establish the stoichiometry of assembly. Electronic absorption spectroscopy revealed a marked increase in molar absorptivity upon self-assembly. These results establish how molecular characterization techniques may be used to distinguish between possible self-assembly outcomes when a given building block may be encoded with directionality that is suitable for more than one geometry. 

Bis-iron(iii)-μ-oxo-porphyrin prisms may be tunedviapost-synthetic tethering. Tethered prisms show enhanced selectivity for the Oxygen Reduction Reaction (ORR) and maintain a cofacial geometry under homogeneous ORR conditions. 

Actinide doping enhances redox chemistry of polyoxomolybdate-alkoxide clusters; the first isolable U(v) polyoxometalate cluster is reported. 

We report on the synthesis and characterization of Mn(III) chloride (MnIIICl3) complexes coordinated with N-oxide ylide ligands, namely trimethyl-N-oxide (Me3NO) and pyridine-N-oxide (PyNO). The compounds are reactive and, while isolable in the solid-state at room temperature, readily decompose into Mn(II). For example, “[MnIIICl3(ONMe3)n]” decomposes into the 2D polymeric network compound complex salt [MnII(µ-Cl)3MnII(µ-ONMe3)]n[MnII(µ-Cl)3]n·(Me3NO·HCl)3n (4). The reaction of MnIIICl3 with PyNO forms varied Mn(III) compounds with PyNO coordination and these react with hexamethylbenzene (HMB) to form the chlorinated organic product 1-cloromethyl-2,3,4,5,6-pentamethylbenzene (8). In contrast to N-oxide coordination to Mn(III), the reaction between [MnIIICl3(OPPh3)2] and 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO) resulted in electron transfer-forming d5 manganate of the [TEMPO] cation instead of TEMPO–Mn(III) adducts. The reactivity affected by N-oxide coordination is discussed through comparisons with other L–MnIIICl3 complexes within the context of reduction potential.