The catalytic ability of ZrO₂/SO₄^2- to promote solventless three-componentcondensation reactions of a diversity of aromatic aldehydes, urea or thoiurea and ethylacetoacetate was studied. Products resulting from Hantzsch and/or Biginelli multi-component reactions are obtained in the presence of solid acid catalysts using the samereactants but different temperature conditions. The sulfated zirconia catalyst can berecovered and recycled in subsequent reactions with a gradual decrease of activity.

Cu(Al)O mixed oxide promotes the formation of 1,2,3-triazoles from an alkyne–azide cycloaddition reaction with excellent yields using an EtOH–H₂O mixture as the solvent under microwave heating.

A practical and efficient one-pot synthesis of novel 1,2,3-triazoles featuring nitrogen, oxygen, and sulfur functionalized pendant arms has been developed. The click reaction of mono-propargyl derivatives supported by aniline, thiophenol, and benzyl alcohol, with sodium azide and p-substituted benzyl halogenides, renders a series of N-substituted-1,2,3-triazoles in good yields under mild reaction conditions. The catalyst system was based in Cu(OAc)₂ · H₂O, sodium L-ascorbate, and 1,10-phenanthroline monohydrate, and all reactions were performed in a mixture H₂O–ethanol (4:1 v/v). Additionally, the preparation of bis-1,2,3-triazoles supported by di-propargylated aniline was carried out, demonstrating the versatility of the present methodology. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]

The 1-benzyl-4-phenyl-1,2,3-triazoles, synthesised from alkyne–azide cycloaddition in presence of mixed Mg/Fe oxides, exhibited excellent properties as corrosion inhibitors.

Sulfated zirconia and SZ/MCM-41 were used as catalysts for the synthesis of β-aminoalcohols via epoxide aminolysis. Sulfated zirconia was prepared by sol-gel andSZ/MCM-41 was obtained by impregnation. Solid catalysts were characterized by XRD,SEM-EDS, UV-Vis, FT-IR pyridine desorption and Nitrogen physisorption. Both acidmaterials were useful as catalysts, even when they were recycled several times. The β-aminoalcohols were characterized by FT-IR, ¹H- and ¹³C-NMR and GC-MS.

An air-stable phosphinito palladium(II) complex (Ph1-Phoxide) has been found to be an efficient catalyst in the formation of C–C bonds. The coupling of terminal alkynes formed gem-1,3-enynes as the only reaction products. Aromatic alkynes can be synthesized from the coupling of terminal alkynes and haloaromatic compounds (Sonogashira coupling). The phosphinito palladium(II) complex also catalyses the coupling between acyl chlorides and terminal alkynes (Sonogashira coupling), furnishing ynones in excellent yields.