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There is a misconception that sustainability is only related to greenhouse gas emissions into the atmosphere, and that this is the only risk to which the planet is exposed. Sustainability is a multidimensional concept and must advance simoutaneously on several fronts, such as the urgent need to increase energy, clean water, clean air, food, mobility, health, and poverty reduction. All the problems of these multi‐dimensions are aggravated by the continuous growth of the world population, mainly in economic and socio‐environmental issues. However, the biggest challenge is to increase the supply of clean energy from renewable sources, as all other dimensions of sustainability depend on energy supply and policy decisions. The consumption of fossil fuels has supplied the current energy demand by approximately 87 %. Still, there are predictions of depletion, and the effects caused on the environment by the production of greenhouse gases bring significant economic losses. In this review, we will address the most common methods for hydrogen production, as well as its main technological applications in organic synthesis and for energy generation. [ABSTRACT FROM AUTHOR]

Reactions that promote the formation of carbon–carbon bonds are of great importance in organic synthesis, since they transform available, relatively inexpensive, and small organic molecules into more complex ones. One of the main protocols used for these transformations are cross‐coupling reactions, and due to their versatility and applications, several efforts have been devoted recently to developing catalysts for such reactions. Supramolecular chemistry has become a major player in this field and encompasses approaches that range from the synthesis of intricate complex architectures that may mimic enzymes, the slight structural modification of commercially available scaffolds, or even repurposing highly available materials such as agarose. This Review discusses the development of supramolecular catalysts for cross‐coupling reactions, focusing mostly on the Suzuki, Heck and Sonogashira reactions promoted by such assemblies. [ABSTRACT FROM AUTHOR]

A stereoselective, base‐free Heck coupling between 1,4‐naphthoquinone and 1H‐1,2,3‐triazole derivatives was reported for the first time. This study shows that depending on the 1,4‐naphthoquinone, the use of an additional base is unnecessary to produce the naphthoquinone‐triazole conjugates. This is also the first example of a Heck coupling of these two cores without using a base as an additive. In this work, sixteen new naphthoquinone‐triazole hybrids were stereoselectively synthetized in good to excellent yields. The reaction mechanism was discussed based on DFT CAM−B3LYP calculations. The first step is the coordination of the arene to the palladium catalyst to form a palladacycle intermediate. After reorganization in this intermediate, the double bond in the arene is restored to proceed with the coupling step and formation of the C−C bond in the rate determining step. The Kozuchi‐Shaik span model was employed to rationalize substituent effects. [ABSTRACT FROM AUTHOR]

The triazole heterocycle is a privileged scaffold in medicinal chemistry, since its structure is present in a large number of biologically active molecules, including several drugs currently in the market. Due to their vast applications, a wide variety of methods are described for their preparation, such as the 1,3‐dipolar cycloaddition and processes involving diazo compounds and diazo transfer reactions. Considering the significant number of contributions from our research group to this chemistry in recent decades, in this account we discuss both the development of new methods for the synthesis of 1,2,3‐triazoles and the preparation of new triazole‐functionalized biologically active molecules using classical approaches. [ABSTRACT FROM AUTHOR]