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The synthesis of polysubstituted spirocyclopropyl oxindoles using a series of rare-earth metal (REM) salts is reported. REMs, in particular Sc(OTf)3, allowed access to the target compounds by a multicomponent reaction with high diastereoselectivity (≤94:6:0:0). Density functional theory calculations on the model reaction are consistent with the observed selectivity and revealed that the special coordinating capabilities and the oxophilicity of the metal are key factors in inducing the formation of one main diastereoisomer. The authors thank Diana Cabrera, Sebastiaan van Liempd, and Juan M. Falcon-Perez from the CIC bioGUNE Metabolomics Platform for performing the UPLC-MS/MS analyses. The authors also acknowledge the Italian Ministry of University and Research (MUR) for Project SI.F.I.PA.CRO.DE. - Sviluppo e industrializzazione farmaci innovativi per terapia molecolare personalizzata PA.CRO.DE. (PON ARS01_00568, CUP: B29C20000360005) and for two doctoral grants. Moreover, the authors thank the University of Calabria and Calabria Region (PAC CALABRIA 2014–2020-Asse Prioritario 12, Azione B 10.5.12 CUP: H28D19000040006) for financial support. This research was also funded by MCIN/AEI/10.13039/501100011033 (Grant PID2021-125946OB-I00 to G.J.-O. and Severo Ochoa Excellence Accreditation CEX2021-001136-S to CIC bioGUNE).

In the continuous effort to identify selective chelators towards bioavailable and toxic metal ions, the potential selectivity of a novel N,O chelating ligand, recently synthesized and claimed to be able to bind to Cu(II) ions forming stable complexes while leaving unaltered the level of essential metal ions, was scrutinized using a combined theoretical and experimental approach. A multistep synthetic procedure was used to synthesize the ligand, whose chelating properties along with the stability of the complexes formed binding Cu(II) and, for comparison, Fe(III) ions were evaluated using potentiometric measurements and UV-Vis spectroscopy. DFT analysis allowed to disclose the structural characteristics of the formed complexes. In the plethora of all the possible structures, a selection of the most reliable ones was achieved by means of a stringent comparison between experimental and simulated UV-Vis spectra. The outcomes of the present investigation demonstrate that the Cu(II) sequestering ability of the ligand is smaller than that towards Fe(III). The strategy used here should allow to check the propensity of ligands in selectively binding metal ions.

We thank the Italian Ministry of University and Scientific Research (MIUR) for a doctoral grant and the University of Calabria for financial support. We also acknowledge the MINECO and FEDER Program (Madrid, Spain, project CTQ2016‐76155‐R) and the Government of Aragon (Zaragoza, Spain. Biological & Computational Chemistry Group. E34_17R) cofunded with Feder 2014‐2020 “Constructing Europe from Aragon”.

A novel series of bio-based polyurethane composite foams was prepared, employing a cellulose-derived polyol for chain extension and cellulose-citrate as a thickener additive. The utilized polyol was obtained from the reduction reaction of cellulose-derived bio-oil through the use of sodium borohydride and iodine. Primarily, we produced both rigid and flexible polyurethane foams through chain extension of the prepolymers. Secondly, we investigated the role of cellulose citrate as a polyurethane additive to improve the mechanical properties of the realized composite materials. The products were characterized by FT-IR spectroscopy and their morphologies were analysed by SEM. Mechanical tests were evaluated to open new perspectives towards different applications.

A series of ketonitrones derived from isatin and indanone (INs) were synthesized and evaluated for their antiproliferative activities against several human cancer cell lines. Then, the antioxidant properties of these substrates were measured by the DPPH test to report their biological activity in terms of their spin trapping action. In particular, one substrate has showed very high biological and scavenging activity, probably due to the strong correlation between its spin trapping activity and structure.

A simple procedure to obtain 1,5-disubstituted 1,2,3-triazoles, using the Er(OTf)3/[mpy]OTf/H2O catalytic system is described. The reaction proceeds through an eliminative azide–olefin cycloaddition (EAOC) offering a highly regioselective approach and good yields (81–94%). The advantages of this method include simple operations of work-up and the ability of the catalytic system to be re-used five times without an evident loss in yield. The role of IL and water were speculated, invoking also a probable ionic self-assembly (ISA) effect.

The use of eco-compatible synthetic procedures in organic reactions and, in particular, in 1,3-dipolar cycloaddition reactions, has recently received a great deal of attention and considerable progress has been achieved in this area in the last years. This review summarizes the approaches currently employed to synthesize heterocyclic compounds by catalyzed 1,3-dipolar cycloadditions in green solvents in the last six years. Our choice to do a selection of the literature from 2014 to 2019 was made considering the absence of a recent review about this period, to our knowledge. Several examples to construct heterocycles by 1,3-dipolar cycloadditions will be discussed in this work subdivided in function of the most important class of non-conventional and green solvents, i.e., ionic liquids (ILs), deep eutectic solvents (DES), and water.

This work was supported by the Ministerio de Ciencia e Innovacion (MICINN) and FEDER Program (Madrid, Spain, project CTQ2013-44367-C2-1-P) and the Gobierno de Aragon (Zaragoza, Spain. D.R.-L. thanks the Spanish Ministry of Education (MEC) for a pre-doctoral grant (FPU program). We thank the Italian Ministry of University and Scientific Research (MIUR) for a doctoral grant and the University of Calabria for financial support.

The synthesis, characterization and evaluation of a new highly efficient organocatalyst, namely (5S)-2,2,3-trimethyl-5-thiobenzylmethyl-4-imidazolidinone hydrochloride has been achieved. The catalyst possesses important structural features that should increase the catalytic efficiency and solubility in polar media. The application of ionic liquid-supported imidazolidinone catalyst in enantioselective Diels–Alder reactions was investigated. The Diels–Alder reactions of several dienes and dienophiles proceeded efficiently in the presence of the catalyst to provide the desired products in a range from moderate to good yields and from good to excellent enantioselectivities. The conformational study confirms that in the transition state the Re face is completely shielded by phenyl ring preferring approach on less hindered Si face. Particularly remarkable is the fact that the entire system IL/HCl 0.01 M/Catalyst can be recovered and reused for up to six runs without appreciable loss of catalytic activity., This work was supported by the Ministerio de Ciencia e Innovación (MICINN) and FEDER Program (Madrid, Spain, project CTQ2013-44367-C2-1-P) and the Gobierno de Aragón (Zaragoza, Spain. D.R.-L. thanks the Spanish Ministry of Education (MEC) for a pre-doctoral grant (FPU program). We thank the Italian Ministry of University and Scientific Research (MIUR) for a doctoral grant and the University of Calabria for financial support.