In recent years, various protocols that facilitate the oxidation of homogeneous Au(I) catalysts have emerged. The latter has allowed the exploration of the synthetic potential associated with the implementation of Au(I)/Au(III) redox cycles. In this context, our research group has contributed to the development of gold-mediated or -catalysed methodologies that enable the formation of C(S)-aryl bonds, utilizing aryldiazonium salts as electrophiles. This article summarizes the state of the art of research in this area and our contribution to it. Furthermore, it reveals a less-explored type of reactivity in which aryldiazonium salts retain the diazo group, resulting in nitrogen heterocyclic compounds.

Keywords: aryldiazonium salts, gold, catalysis, ascorbic acid, coupling

Currently, organometallic compounds have gained significant attention due to their diverse applications. Among them, pincer compounds stand out for their high stability, making them ideal candidates as catalysts and for the development of new metallodrugs. This review explores key aspects of these compounds, including synthetic routes,
a detailed description of their structure and the contributions of our research group in homogeneous catalysis, electrocatalysis, and medicinal chemistry, focusing on para-functionalized POCOP pincer compounds.

Keywords: organometallic compounds, POCOP pincer compounds, homogeneous catalysis, mettallodrugs, electrocatalysts

Cation derived from the tetramethylpiperidine-N-oxoammonium (TEMPO+) have found several applications in organic synthesis, mainly as oxidizing agents for obtain-ing carbonyls from alcohols. TEMPO+ has also proven to be highly efficient and selective for promoting C(sp3)–H functionalization of N-heterocycles. Recently, it was dis- covered that can act as Lewis acid in electrophilic addition reactions, Nazarov and Ferrier rearrangement. Owing to their non-metallic nature, high stability, and low toxicity, TEMPO+ salts are highly valuable and affordable reagents. In this article, we will briefly explore the evolution of the chemistry of the TEMPO+ and its application in different chemical transformations. We will show some representative examples and describe certain key reaction mechanisms to highlight the privileged role that TEMPO+ plays in organic synthesis.

Keywords: TEMPO+ cation, C(sp3)–H functionalization, Lewis acid, Ferrier rearrangement, transition-metal-free

The use of a catalyst and H₂ or hydrogen sources for the reduction of oxygen content in a variety of materials is known as catalytic hydrodeoxigenation (HDO). The aim of its use in biomass-derived materials is the reduction of oxygen content. The ideal products are sustainable hydrocarbons, neutral in carbon; however, also some other useful products can be obtained on the way. This paper presents a general overview in the field along with examples related to fuel production and value-added products.

Keywords: hydrodeoxigenation, biomass, catalysis, hydroprocess

Vanadium, the element discovered by Andrés Manuel del Río, has an aqueous chemistry very suitable for
laboratory experiments, in which the availability of different contiguous and accessible oxidation states, the
acid-base behavior of its compounds or the coordination chemistry and spectroscopic properties of its complexes
can be exploited. In addition to its didactic value, it is also attractive due to the beautiful color of its
combinations. This contribution describes activities involving vanadium compounds that have been carried
out in advanced inorganic chemistry courses at our University for years. The main objective is to have students
record and analyze the electronic spectra of species of the metal with different d-configurations.

Keywords: vanadium, laboratory experiments, rédox, UV-VIS, Andrés Manuel del Río

Chemistry has been integrated through a system of scientific and industrial practices developed over centuries.
It is pragmatic, experimental, and relational. Drawing on W. Jensen’s ideas, his chemical revolutions, and his
hierarchy of composition/structure of substances, as well as the IUPAC characterization of the chemical elements
as atomic nucleus, it is relevant to consider replacing the concept of atom with that of the mononuclear molecule
in chemistry teaching.

Keywords: Molecules, atoms, uninuclear molecules, chemical practices, chemistry teaching

Modesto Bargalló Ardévol (Sabadell, Spain, 1894 – Mexico City, Mexico, 1981) is a prominent but unknown figure in the history of physical and chemical sciences and their teaching. Until his exile to Mexico in 1939 due to the Spanish Civil War, he carried out a prolific career in Spain improving the scientific training of teachers. In Mexico, he continued his active teaching and publishing work, becoming a distinguished historian of chemistry. Actually, Bargalló is the only Spanish chemistry historian who has received the Dexter Award from the American Chemical Society. This article summarizes the current historical research on his life and work in order to recover and highlight his legacy for the didactics and the history of science.

Keywords: History of Science, Didactics of Science, Modesto Bargalló, Scientific Biographies, Science Teachers

Some aspects of the life and scientific work of Andrés Manuel del Río (1764–1849) are presented. He was a distinguished mining engineer, scientist, and professor born in Ma- drid, but he remains relatively unknown in Spain because he carried out most of his work in Mexico. He stood out for his contributions to mineralogy, the training of mining engi- neers, and, mainly, for the discovery of the chemical element he named erythronium, which would later become known as vanadium. That is the only non-radiactive element discovered outside Europe. Among many other activities, del Río served as a deputy in Madrid during the Constitutional Triennium (1820–1823), representing New Spain. The text also includes some of the recognitions his work has received and expresses the hope that he will gain greater recognition within the chemical community and among the gene- ral public.

Keywords: Andrés Manuel del Río, Eritronio, Ilustración Española, Vanadio