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The radical reactions of dimethylsulfoxide (DMSO) and tetrahydrothiophene-1-oxide (THTO) with reactive oxygen species (ROS) in the presence of a nitroxide radical scavenger have been evaluated both synthetically and in analytical practice. Fenton-mediated generation of oxygen-centred radicals produced several unusual products that reflect the fragmentation and ring-opening radical mechanisms of DMSO and THTO respectively. Addition of pollution-derived ROS to DMSO/THTO nitroxide solutions produced LC-MS detectable amounts of the same products isolated from the larger-scaled Fenton reactions. For air pollution analysis, these results highlight the complexity surrounding DMSO reactivity and fragmentation, and indicate that THTO produces simpler outcomes that should facilitate analysis of the processes involved.

The synthesis and crystal structures of a series of Ln(III) (Ln = Gd, Nd, Yb as well as Y) complexes of a bis-β-diketone ligand incorporating a 1,3-substituted phenyl ring between its two β-diketone domains (1,1′-(1,3-phenylene)bis(4,4-dimethylpentane-1,3-dione), H2L1) is reported. The crystal structures show the complexes are seven coordinate in the solid state with the general formula [Ln2L13(solvent)2]. The photophysical properties of the complexes were explored in both solution and the solid state, which show an increase in coordination number in solution.

Nature builds simple molecules into highly complex assemblies, which are involved in all fundamental processes of life. Some of the most intriguing biological assemblies are those that can be precisely reconfigured to achieve different functions using the same building blocks. Understanding the reconfiguration of synthetic self-assembled systems will allow us to better understand the complexity of proteins and design useful artificial chemical systems. Here we have prepared a relatively simple system in which two distinct self-assembled structures, a [Fe2L3]4+ helicate and a [Fe4L6]8+ cage that are formed from the same precursors, coexist at equilibrium. We have measured the rates of interconversion of these two species and propose a mechanism for the transformation.

A bis-β-diketone ligand incorporating a 3,5-substituted pyridine ring between its two β-diketone domains (1,1′-(pyridine-3,5-diyl)bis(4,4-dimethylpentane-1,3-dione), H2L1) and its interaction with three divalent cations (Cu2+, Zn2+ and Pd2+) is reported. Charge neutral dinuclear metallocycles of type [M2L12] were obtained in each case and their X-ray structures determined. [Pd2L12] incorporates two square-planar O4-coordinated metal centres. The zinc(II) and copper(II) complexes contain five-coordinate O4N1-metal centres in which the pyridyl nitrogen from adjacent [M2L12] metallocycles coordinates apically forming two-dimensional coordination polymers of type {[Zn2L12]n(dmf)n} and {[Cu2L12]n(dmf)n}. Desolvation of the coordination polymers led to loss of crystallinity.

The rational, deliberate design of supramolecular architectures is of great importance for the discovery of complex materials. A three-dimensional cubic halogen-bonded network has been prepared by combination of an octahedral metal-containing halogen bond acceptor and a linear ditopic donor. This material displays α-Po pcu topology and is seven-fold interpenetrated. This is the first neutral, metal-containing three-dimensional halogen-bonded network to be reported.

Correction for ‘Straightening out halogen bonds’ by Caitlin J. Setter et al., CrystEngComm, 2020, 22, 1687–1690, DOI: 10.1039/D0CE00176G.