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The preparation of a Zn5ionic coordination cluster 1as a perchlorate salt is described containing four ditopic redox-active ligands in dianion-radical oxidation states. The structure of the complex features five Zn2+ions in three different coordination geometries: distorted trigonal bipyramidal, distorted square pyramidal, and distorted octahedral. Single crystal X-ray diffraction data, variable temperature magnetic susceptibility experiments, and broken symmetry density functional theory calculations from the cluster are interpreted to describe the magnetic properties of 1in terms of a model comprised of intramolecular ferromagnetic coupling between the four radical ligands in the cluster to give an S= 2 ground state and intermolecular antiferromagnetic interactions between the S= 2 molecules in a one-dimensional antiferromagnetic chain, as described by Fisher.

The synthesis, characterisation and properties of several divalent metal complexes (Co, Ni, Pd) containing 2-oxazoline ligands L1–L3, appended with long chain alkyl and/or ester groups, is reported. The X-ray crystal structure aspects of one such complex, trans-PdCl2(rac-2-heptadecyl-4,5-dihydro-5-methyl-2-oxazole)2(i.e. PdCl2(L1)2: 3), is described. This latter material contains one of the longest alkyl chains to be crystallographically characterised appended to an oxazoline ligand. The complexes reported herein represent the first transition metal derivatives of these high molecular weight, long chain and presumably low polarity monodentate oxazoline ligands. A combination of spectral and theoretical calculations (semi-empirical PM6(tm) level of theory) are used to support the proposed structure in the case of the hydrates of NiCl2and CoBr2complexes derived from L1. A trio of PdCl2complexes of the ligand set are likewise detailed. Complex 3is shown to be a useful pre-catalyst for the promotion of a Heck coupling reaction between bromobenzene and styrene under typical conditions.

Frustrated Lewis pairs (FLPs) derived from R3P (R = otol, Mes) and B(C6F5)3or AlX3(X = halide, C6F5) add to ethylene. Similarly, the P/B FLP adds across propylene, whereas the P/Al systems react with propylene to effect propylene dimerization via a C–H bond activation and C–C bond formation, affording an Al-bound 2-methylpentene complex.

Al(C6F5)3/R3P [R = tert-butyl (tBu), mesityl (Mes), naphthyl (Nap)] frustrated Lewis pairs react with N2O to form species having the formula R3P(N2O)Al(C6F5)3, which react with additional alane to generate proposed frustrated radical ion pairs formulated as [R3P·][(μ-O·)(Al(C6F5)3)2] that can activate C–H bonds. For R = tBu, C–H activation of a tBu group affords [tBu2PMe(C(CH2)Me)][(μ-OH)(Al(C6F5)3)2]. In the case of R = Mes, the radical cation salt [Mes3P·][(μ-HO)(Al(C6F5)3)2] is isolated, while for R = Nap, the activation of toluene and bromobenzene gives [(Nap)3PCH2Ph][(μ-OH)(Al(C6F5)3)2] and [(Nap)3PC6H4Br][(μ-HO)(Al(C6F5)3)2], respectively.

A series of UV active benzophenone ([C6H5COC6H4-O-(CH2)n-N+Me2R][X–]; 4, R = C12H25, n= 3, X–= Br–; 5a–c, R = C18H37, n= 3, X–= Cl–, Br–, I–; 6a–c, R = C18H37, n= 4, X–= Cl–, Br–, I–; 7a–c, R = C18H37, n= 6, X–= Cl–, Br–, I–) terminated C12and C18quaternary ammonium salts (QACs) were prepared by thermal or microwave-driven Menshutkin protocols of the appropriate benzophenone alkyl halide (1a–c, 2a–c, 3a–c) with the corresponding dodecyl- or octadecyl N,N-dimethylamine. All new compounds were characterized by NMR spectroscopy, HRMS spectrometry, and, in one instance (4), by single-crystal X-ray crystallography. Representative C12and C18benzophenone QACs were formulated into 1% (w/v) water or water/ethanol-based aerosol spray coatings and then UV-cured onto plastic substrates (polypropylene, polyethylene, polystyrene, polyvinyl chloride, and polyether ether ketone) with exposure to low to moderate doses of UV (20–30 J cm–2). Confirmation as to the presence of the coatings was detected by advancing water contact angle measurements, which revealed a more hydrophilic surface after coating. Further confirmation was gained by X-ray photoelectron spectroscopy analysis, time of flight secondary ion mass spectrometry, and bromophenol blue staining, all of which showed the presence of the attached quaternary ammonium molecule. Analysis of surfaces treated with the C18benzophenone 5bby atomic force microscopy and surface profilometry revealed a coating thickness of ∼350 nm. The treated samples along with controls were then evaluated for their antimicrobial efficacy against Gram-positive (Arthrobactersp., Listeria monocytogenes) and Gram-negative (Pseudomonas aeruginosa) bacteria at a solid/air interface using the large drop inoculum protocol; this technique gave no evidence for cell adhesion after a 3 h time frame. These antimicrobial materials show promise for their use as coatings on plastic biomedical devices with the aim of preventing biofilm formation and preventing the spread of hospital acquired infections.