This submission was created using the RSC Article Template (DO NOT DELETE THIS TEXT) (LINE INCLUDED FOR SPACING ONLY -DO NOT DELETE THIS TEXT)Vinylbenzyl chloride was grafted onto PVDF and FEP polymer films using the radiation-grafting methodology. Subsequent reaction with trimethylamine and ion-exchange with potassium hydroxide yields alkaline anion-exchange membranes that are capable of conducting hydroxide ions; such membranes may be suitable for use in low temperature direct methanol fuel cells for portable devices. The PVDF based materials underwent an undesirable degradation and were found to be less suitable for this class of membrane. FEPbased materials exhibited superior structural stability, conductivities up to 0.02 S cm -1 at room temperature, and good retention of ionexchange capacities when treated in water at 60°C.

Vinylbenzyl chloride (VBC) has been radiation grafted onto both PVDF and FEP fluoropolymer films. Subsequent amination with trimethylamine and ion-exchange to give the hydroxide ion forms yield anion-exchange membranes (AEMs) suitable for use in low temperature direct methanol fuel cells (DMFCs) for portable applications. The polymeric backbone of the PVDF-based materials degrades on alkaline treatment; significantly, this is not the case for the FEPbased materials.Two obstacles inhibiting application of DMFCs are (i) the relatively low activity and high costs of methanol electrooxidation catalysts and (ii) methanol crossover through current generation proton-exchange membranes (PEMs). 1Liquid alkaline fuel cells (AFCs) have been developed to a significant level; a principle reason for this is that the catalysts generally perform better in alkaline conditions and at lower loadings, and a wider range of catalyst may be used.2 McLean et al. observed in a recent review on AFCs that there is a great potential in the production of a polymer alkaline membrane fuel cell. 3 There has recently been growing interest in the literature on using AEMs in fuel cells, 4 an example being recent work by Agel et al. on polyethylene oxide membranes containing dissolved potassium hydroxide. The stability of a commercially available AEM containing benzyltrimethyl ammonium groups radiation-grafted onto PTFE membranes in aqueous sodium hydroxide solution (6 mol dm -3 ) was good up to temperatures between 50 -60°C. 5DMFCs operating at ambient conditions have been identified as ideal for replacing batteries for portable applications (laptops, cellular phones, man-portable power packs) due to the ever increasing power demands (especially with the imminent introduction of mobile broadband communications) that will surpass levels projected for secondary battery technology. 6DMFCs are amenable to portable applications due to the good power density of the dense and easily replenished liquid fuel (methanol). Under alkaline conditions the fuel cell reactions for the anode (1) and the cathode (2) are:Product water is formed at the anode, in contrast to a cell containing a PEM. The use of an alkaline AEM could resolve the problem of methanol crossover from the anode to the cathode as the electro-osmotic water transport occurs in the opposite direction; the use of cheaper catalysts would also be feasible. Polymer alkaline exchange membranes have been reported to function in the presence of carbonate species and could yield a solution to the problem of carbonate build-up in liquid-based AFCs. 3In fuel cell membrane research the effort has been concentrated on PEMs, 7 with the focus being the development of cheaper alternatives to the industry standard Nafion ® produced by Dupont. A large proportion of this effort has examined styrene radiation-grafting onto partially fluorinated films 8,9 such as poly(vinylidene fluoride) (PVDF, -[CH 2 CF 2 ] n -) and fully fluorinated films 9 such as poly(tetrafluoroethene-cohexafluoropropylene) (FEP, -[CF 2 CF 2 ...

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[2+3] Cycloaddition of nitrones to the nitrile ligands in the complexes cis- or trans-[PtCl2(PhCN)2] occurs under ligand differentiation and allows for selective synthesis of complexes of the type cis- or trans-[PtCl2(oxadiazoline)(PhCN)]. Microwave irradiation enhances the reaction rates of the cycloaddition considerably and further favours the selectivity towards the mono-cycloadduct with respect to thermal conditions, because the first cycloaddition is accelerated to a higher extent than the second one. Reaction of the trans-substituted mono-oxadiazoline complexes with a nitrone different from the one used for the first cycloaddition step gives access to mixed bis-oxadiazoline compounds of the composition trans-[PtCl2(oxadiazoline-a)(oxadiazoline-b)]. The corresponding cis-configured complexes, however, do not undergo further cycloaddition. All reactions described occur without isomerisation of the stereochemistry around the platinum center, independently of whether thermal or microwave heating is applied.

published as an Advance Article on the web 8th May 2003[2 ϩ 3] Cycloaddition of N-methyl-C-phenylnitrone to transition metal coordinated (E )-cinnamonitrile occurs exclusively at the nitrile C᎐ ᎐ ᎐ N bond, leading to ∆ 4 -1,2,4-oxadiazoline complexes, from which the heterocyclic ligand can be released and isolated in high yield. In contrast, the reaction of the nitrone with free cinnamonitrile involves the C᎐ ᎐ C bond only, yielding a diastereomeric mixture of isoxazolidine-4-carbonitriles. Microwave irradiation enhances the reaction rates of both transformations considerably, without changing their regioselectivity with respect to the thermal reactions. The two nitrile ligands in complexes of the type [MCl 2 (cinnamonitrile) 2 ] (M = Pt or Pd) are significantly different in reactivity. Thus, short-time microwave irradiation allows for the selective synthesis of the mono-cycloaddition product [PtCl 2 (cinnamonitrile)(oxadiazoline)], even in the presence of an excess of nitrone. Using longer irratiation times, this complex can be further transformed into the bis-cycloaddition product [PtCl 2 (oxadiazoline) 2 ]. The latter compound is also produced when thermal heating is applied, however, the formation of the mono-cycloaddition product fails to be selective under thermal conditions.