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Cyclohexane is a cycloalkane with the ... Producers of cyclohexane account for approximately 11.4% of global demand for benzene. [8] The reaction is highly exothermic ...
Aromatization is a chemical reaction in which an aromatic system is formed from a single nonaromatic precursor. Typically aromatization is achieved by dehydrogenation of existing cyclic compounds, illustrated by the conversion of cyclohexane into benzene. Aromatization includes the formation of heterocyclic systems. [1]
The most common reactions of benzene involve substitution of a proton by other groups. [72] Electrophilic aromatic substitution is a general method of derivatizing benzene. Benzene is sufficiently nucleophilic that it undergoes substitution by acylium ions and alkyl carbocations to give substituted derivatives.
Useful reactions of this diene are cycloadditions, such as the Diels-Alder reaction. [2] Conversion of cyclohexa-1,3-diene to benzene + hydrogen is exothermic by about 25 kJ/mol in the gas phase. [3] [4] cyclohexane → cyclohexa-1,3-diene + 2 H 2 (ΔH = +231.5 kJ/mol; endothermic) cyclohexane → benzene + 3 H 2 (ΔH = +205 kJ/mol; endothermic)
The complete hydrogenation of benzene to cyclohexane via 1,3-cyclohexadiene and cyclohexene is exothermic; 1 mole of benzene delivers 208.4 kJ (49.8 kcal). Hydrogenation of one mole of double bonds delivers 119.7 kJ (28.6 kcal), as can be deduced from the last step, the hydrogenation of cyclohexene.
Birch reduction of benzene, also available in animated form. The reaction is known to be third order – first order in the aromatic, first order in the alkali metal, and first order in the alcohol. [4] This requires that the rate-limiting step be the conversion of radical anion B to the cyclohexadienyl radical C. Birch reduction of anisole.
The reaction product is a derivative of benzene. Scheme 1. Bergman cyclization. The reaction proceeds by a thermal reaction or pyrolysis (above 200 °C) forming a short-lived and very reactive para-benzyne biradical species. It will react with any hydrogen donor such as 1,4-cyclohexadiene which converts to benzene.
This reaction is related to several classic named reactions: The acylated reaction product can be converted into the alkylated product via a Clemmensen or a Wolff-Kishner reduction. [17] The Gattermann–Koch reaction can be used to synthesize benzaldehyde from benzene. [18] The Gatterman reaction describes arene reactions with hydrocyanic acid ...