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Halogenation of benzene where X is the halogen, catalyst represents the catalyst (if needed) and HX represents the protonated base. A few types of aromatic compounds, such as phenol, will react without a catalyst, but for typical benzene derivatives with less reactive substrates, a Lewis acid is required as a catalyst.
The chemical complexity of coffee is emerging, especially due to observed physiological effects which cannot be related only to the presence of caffeine. Moreover, coffee contains an exceptionally substantial amount of antioxidants such as chlorogenic acids, hydroxycinnamic acids, caffeine and Maillard reaction products, such as melanoidins. [3]
The overall reaction mechanism, denoted by the Hughes–Ingold mechanistic symbol S E Ar, [3] begins with the aromatic ring attacking the electrophile E + (2a). This step leads to the formation of a positively charged and delocalized cyclohexadienyl cation, also known as an arenium ion, Wheland intermediate, or arene σ-complex (2b).
In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. [1] This kind of conversion is in fact so common that a comprehensive overview is challenging.
The content of phenols in rosé wine (82 mg/100 ml) is intermediate between that in red and white wines. In winemaking, the process of maceration or "skin contact" is used to increase the concentration of phenols in wine. Phenolic acids are found in the pulp or juice of the wine and can be commonly found in white wines which usually do not go ...
America's national parks and other federal lands are in danger of falling into disrepair following the firings of thousands of federal employees by the current administration, experts said.
A chlorophenol is any organochloride of phenol that contains one or more covalently bonded chlorine atoms. There are five basic types of chlorophenols (mono- to pentachlorophenol) and 19 different chlorophenols in total when positional isomerism is taken into account. Chlorophenols are produced by electrophilic halogenation of phenol with ...
North Korean leader Kim Jong Un said the country has come a long way in building a powerful army but weapons without ideology are simply "ironware", as he stressed loyalty to some of its most ...