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Acyclic and cyclic unsaturated carboxylic acids 1 to 4 are most easily converted to unsaturated dicarboxylic acids 5 to 8 by oxidative coupling of their diene- or triene-diolates by 1,2-diiodoethane. This procedure improves formerly reported oxidations by iodine or silver salts.

Substituted 2-cyclohexenones 4 to 7 and hexaxydronaphthalenones and hexahydroindenones 13 to 18 are prepared by tandem Michael-Dieckmann addition of lithium dienediolates of acyclic and alicyclic unsaturated carboxylic acids to the lithium salts of the same or other unsaturated carboxylic acids.

Transition metals are powerful three-dimensional templates, which can gather various functionalized ligands and orient them in a precise fashion so that complex multicomponent molecular systems can be obtained without constructing covalently-assembled edifices. The compounds thus prepared exhibit precise chemical or physical functions, which are governed by the design of the system. The construction of one-dimensional molecules around ruthenium(II) or osmium(II), using rigid ligands attached to the desired electroactive species, leads to systems that are able to undergo charge separation after photonic excitation. In other related compounds, a ruthenium(II)-based chromophore is, for example, connected to an osmium(II) complex by means of rod-like bridging ligand, thereby ensuring strict control over the Ru···Os distance. By tuning the length and the electronic properties of the bridge, one can control the efficiency of the electronic energy transfer between the two chromophores. In particular, the use of a bis-cyclometallating ligand is very conducive to energy transfer and allows the observation of this process up to a Ru…Os distance of ≈20 A. By combining the building blocks of these inorganic systems with appropriate porphyrins, long-range (centre-to-centre distance between the donor and the acceptor porphyrins ≈30 A) and relatively long-lived photoinduced charge separation has been demonstrated. Finally, with copper(I) as the template, compounds of the rotaxane family are obtained, which consist of a coordinating ring threaded by a string-like component. If this acyclic fragment is end-functionalized by two bulky stoppering groups and if it incorporates two different coordination sites (a bi- and a terdentate chelate site), novel dynamic properties are observed. The movement of a given fragment of the molecule is triggered by changing the metal oxidation state. This one-dimensional motion of the ring along the string on which it is threaded is controlled by redox manipulation, resulting in a primitive molecular machine.

Functional catenanes and threaded systems able to perform controllable mechanical motions are ideally suited for the design of molecular devices displaying mechanical, electronic, information or sensing functions. These systems have been extensively studied in solution phase and numerous examples of stimuli-driven molecular shuttles have been reported. However, for fully developing their potential applications, they must be interfaced with the macroscopic world. To achieve this objective, in the last few years catenanes and rotaxanes have been organized over surfaces in the form of chemisorbed monolayers or physisorbed monolayers, multilayers and thin films. This tutorial review summarizes the different techniques for the deposition on surfaces and characterization of switchable catenanes and rotaxanes, and highlights the properties of these new functional surfaces and their potential applications.

A new cyclohexyl based fluorescent anion receptor, is able to recognize maleate versus fumarate both as their TMA salts. Costero Nieto, Ana Maria, Ana.Costero@uv.es ; Colera Llavata, Manuel, Manuel.Colera@uv.es ; Gaviña Costero, Pablo, Pablo.Gavina@uv.es ; Gil Grau, Salvador, Salvador.Gil@uv.es

A suitable method for the preparation of the chiral mixed O/S ligands 1,2-sulfinyl thiols is described. These compounds have then been used as a chiral proton source in the enantioselective protonation of 2-methyl tetralone enolate and the results are compared with those obtained from the analogous alcohols. A theoretical model is proposed to explain the different behaviors exhibited in the protonation reaction for each of these proton sources. Configurational assignments for the new chiral thiols have been carried out by means of X-ray analysis.