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2-oxazolines are known for a long time but only recently studies concerning their use as catalyst for asymmetric synthesis have gained enormous attention. The synthesis of copolymers involving 2-oxazoline ring-monomers is known. Functionalized 2oxazoline-homopolymers presents different medicinal and biological applications. In this study we present the synthesis of optically active alkynyl-pyridyl-oxazoline monomers to be used as precursors of helical polymers. Depending on the nature of the substituent attached to the arylacetylenic unity helical preferentially oriented (P or M) polymers can be obtained. These kind of helical polymers may be employed in the molecular and/or ion recognition. Moreover the polymers containing the pyridyl-oxazoline unity will be employed for metal complexation and the resulting organometallics will be explored for recoverable catalysts.

We are grateful to Scientific Association ProteoMass (Portugal), Xunta de Galicia (Spain) for a research contract under project 09CSA043383PR (JFL) and I2C postdoctoral program (C.N). Authors are also grateful for the financial and structural support offered by the University of Sao Paulo through the NAP-CatSinQ (Research Core in financial support.

The Morita-Baylis-Hillman (MBH) reaction is well known for providing valuable building blocks in organic synthesis. In the last few years it has been demonstrated that not only the MBH adducts itself can be useful intermediates, but also, its derivatives. The corresponding esters of MBH adducts (acetates, in most cases) have been extensively described in the literature due to its particular reactivity towards the attack of different nucleophiles (Scheme 1).

Selective hydrogenation of alkynes is an important transformation in organic synthesis and, the development of methodologies to obtain olefins is still challenging. 1 Nowadays, there is a growing demand for process that allows transformations on highly functionalized molecules as synthetic intermediates for pharmaceutical products. In that sense, the preparation and modification of propargylamines has gained popularity in recent years. 2 Propargylamine derivates can be synthesized by A 3 coupling, which is a multicomponent reaction between an aldehyde, an amine and an alkyne. Palladium is the most widely used catalysts to perform hydrogenation of alkynes but the evaluation of the catalytic activity and selectivity of new catalysts is usually made with simple alkynes. Herein, we report the synthesis of functionalized propargylamines, and the development of new highly active and selective magnetic Pd nanocatalyst 3 to perform the partial hydrogenation of these compounds. In the last ten years, the use of magnetic nanoparticles (MNPs) as catalyst supports brought a new perception of catalysis in terms activity, selectivity and sustainability. 4 However, Pd supported on MNPs still remains scarcely explored in the hydrogenation of alkynes.

The Diels-Alder reactions of para-benzoquinones and simple dienes produce cycloadducts which serve as important intermediates for the synthesis of bioactive terpenes. 1 These cycloadditions are usually conducted in organic solvents (such as MeOH and CH2Cl2), for several days, or with Lewis acid catalysis in CH2Cl2. The usual Lewis acid catalysts are very efficient, but require anhydrous and oxygen-free conditions. Thus, there is ample scope for improved methodologies for the efficient execution of the Diels-Alder reaction. We have now developed a mild solvent-free protocol for the promotion of these Diels-Alder reactions, catalysed by a mixture of FeCl3 on Aerosil ® silica (AS ® ).

The induction of chirality still a very intricate and exciting research area being the organocatalysis one of the most recent focus of investigation. Helical chirality is present on nature. Inspired on this asymmetric concept, some synthetic helical compounds, especially polymers have ben applied for asymmetric synthesis, enantiomeric separations and studies related to the properties of liquid crystalline compounds. The preferential helicity of a polymer can be induced by the nature of the pendant molecular residue. Many applications have ben found for this kind of molecules. Recently we have proposed the synthesis of helical polymers for catalytic application since the recovery of a polymer from the reaction media can be easier then a smaller parent compound. In addition, we wonder if the helicity could play some role on the chirality induction. In this way, we designed and synthesized a proline-based helical polymer and subjected it to aldol reaction.