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Templates are widely used to arrange molecular components so they can be covalently linked into complex molecules that are not readily accessible by classical synthetic methods (1-7). Nature uses sophisticated templates such as the ribosome, whereas chemists use simple ions or small molecules. But as we tackle the synthesis of larger targets, we require larger templates--which themselves become synthetically challenging. Here we show that Vernier complexes can solve this problem: if the number of binding sites on the template, [n.sub.T], is not a multiple of the number of binding sites on the molecular building blocks, [n.sub.B], then small templates can direct the assembly of relatively large Vernier complexes where the number of binding sites in the product, [n.sub.P], is the lowest common multiple of [n.sub.B] and [n.sub.T] (refs 8, 9). We illustrate the value of this concept for the covalent synthesis of challenging targets by using a simple six-site template to direct the synthesis of a 12-porphyrin nano-ring with a diameter of 4.7 nm, thus establishing Vernier templating as a powerful new strategy for the synthesis of large monodisperse macromolecules., The principle behind all Vernier systems is the formation of a moire pattern. Moire patterns are observed on a wide range of length scales whenever two non-commensurate periodicities are superimposed. [...]

A Keggin-type POM is attached togold or glassy carbon surfacesby electro(chemical) or peptidic coupling. In addition to demonstratingthe robust attachment of the POMs (by electrochemistry, XPS, and IRRAS),the surface concentration, layer thickness, and rate constant forelectron transfer from the surface to the POMs have been measured.The use of such complementary techniques is mandatory to characterizethe modified electrodes properly. Whatever the grafting method, experimentalconditions are found to allow monolayer or submonolayer coverage.Besides covalently grafted species, additional electrostatically bondedPOMs are present in the film. Cathodic polarization allows removingthem to get a grafted film that is stable with time and potential,which is a requirement in the design of molecular memories. [ABSTRACT FROM AUTHOR]

A polyoxometalate-based molecular triangle has been synthesized through the metal-driven self-assembly of covalent organic/inorganic hybrid oxo-clusters with remote pyridyl binding sites. The new metallomacrocycle was unambiguously characterized by using a combination of (1)H NMR spectroscopy, 2D diffusion NMR spectroscopy (DOSY), electrospray ionization travelling wave ion mobility mass spectrometry (ESI-TWIM-MS), small-angle X-ray scattering (SAXS) and molecular modelling. The collision cross-sections obtained from TWIM-MS and the hydrodynamic radii derived from DOSY are in good agreement with the geometry-optimized structures obtained by using theoretical calculations. Furthermore, SAXS was successfully employed and proved to be a powerful technique for characterizing such large supramolecular assemblies., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Polyoxometalates (POMs) are attractive candidates for the rational design of multi-level charge-storage materials because they display reversible multi-step reduction processes in a narrow range of potentials. The functionalization of POMs allows for their integration in hybrid complementary metal oxide semiconductor (CMOS)/molecular devices, provided that fine control of their immobilisation on various substrates can be achieved. Owing to the wide applicability of the diazonium route to surface modification, a functionalized Keggin-type POM [PW11 O39 {Ge(p-C6 H4 -CC-C6 H4 -${{\rm N}{{+\hfill \atop 2\hfill}}}$)}](3-) bearing a pending diazonium group was prepared and subsequently covalently anchored onto a glassy carbon electrode. Electron transfer with the immobilised POM was thoroughly investigated and compared to that of the free POM in solution., (Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)