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Effect of different reaction parameters on the catalytic activity of β-tetrabrominated meso-tetra(para-tolyl)porphyrinatomanganese(III), MnT(4-CH₃P)PBr₄(OAc), for oxidation of different sulfides and hydrocarbons with tetra-n-butylammonium hydrogen monopersulfate (TBAHS) has been studied. In oxidation of sulfides, the chemoselectivity of reaction has been significantly changed in THF as the solvent compared with the common organic solvents. Also, using nitrogenous bases bearing electron-withdrawing groups (-Cl or -CN) clearly increased the ratio of sulfoxide to sulfone relative to the electron-donating ones. Catalytic oxidation of olefins with TBAHS was conducted in protic and aprotic solvents and acetonitrile has been found as the best solvent. A significantly large difference was found between the co-catalytic activity of imidazole (ImH) and pyridine in comparison with that observed in dichloromethane. The competitive oxidation of cis- and trans-stilbene suggests the presence of a high valent manganese oxo as well as a six coordinate (ImH)MnT(4-CH₃P)PBr₄(HSO₅) species as the active oxidants in acetonitrile.

Some people think that carbon and sustainable development are not compatible. This textbook shows that carbon dioxide (CO₂) from the air and bio-carbon from biomass are our best allies in the energy transition, towards greater sustainability. We pose the problem of the decarbonation (or decarbonization) of our economy by looking at ways to reduce our dependence on fossil carbon (coal, petroleum, natural gas, bitumen, carbonaceous shales, lignite, peat). The urgent goal is to curb the exponential increase in the concentration of carbon dioxide in the atmosphere and hydrosphere (Figures 1.1 and 1.2) that is directly related to our consumption of fossil carbon for our energy and materials The goal of the Paris agreement (United Nations COP 21, Dec. 12, 2015) of limiting the temperature increase to 1.5 degrees (compared to the pre-industrial era, before 1800) is becoming increasingly unattainable (Intergovermental Panel on Climate Change (IPCC), report of Aug. 6, 2021). On Aug. 9, 2021 Boris Johnson, prime minister of the United Kingdom, declared that coal needs to be consigned to history to limit global warming. CO₂ has an important social cost…

Today, fossil carbon provides us with fuels (energy), polymers (packaging, insulating and building materials, household utensils, glues, coatings, textiles, 3D-printing inks, furnitures, vehicle parts, toys, electronic and medical devices, etc.) and biologically active substances (drugs (Chapter 9), flavorings, fragrances, food additives, plant protection products, etc.). In this chapter we discover the modern materials of our civilization which are very often polymers derived from oil. They are referred to as “plastics” (annual world production: 380 × 10⁶ tons). Their production consumes 8% of the crude oil extracted (ca. 5 billion tons per year). An increasing part of the plastics originates from renewable resources (less than 10% today, see Section 11.10, bio-sourced plastics). Plastics make life easy for us, but at the underestimated cost of damage to our environment (Figure 8.1) and our health. They contaminate the hydrosphere and the agricultural soil. The atmosphere is also contaminated by microplastics…

Syngas is a mixture of carbon monoxide (CO) and molecular hydrogen (H₂) that can be converted into a host of industrial feedstocks including fuels such as gasoline, fuel oil and kerosene. We examine what are the most abundant sources of these two gases and describe some important transformations that continue to fascinate scientists because, with a reactant as simple as CO, which contains only one carbon atom, catalysts allow to condense it with H₂ and to form C–C bonds even though all oligomers of the (CO)_n type (n = 2, 3, …) are kinetically and thermodynamically unstable. Let us recall here that thanks to photosynthesis, Nature builds C–C bonds (e.g. D-glucose) from CO₂ and H₂O and solar light! (Section 1.4.2, reaction (1.8), Figure 1.10)…