Search results
Results from the WOW.Com Content Network
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]
Cyclohexane is a colourless, flammable liquid with a distinctive detergent-like odor, reminiscent of cleaning products (in which it is sometimes used). Cyclohexane is mainly used for the industrial production of adipic acid and caprolactam, which are precursors to nylon. [5] Cyclohexyl (C 6 H 11) is the alkyl substituent of cyclohexane and is ...
The most widely practiced example of this reaction is the ethylation of benzene. Approximately 24,700,000 tons were produced in 1999. [ 73 ] Highly instructive but of far less industrial significance is the Friedel-Crafts alkylation of benzene (and many other aromatic rings) using an alkyl halide in the presence of a strong Lewis acid catalyst.
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.
He used a Friedel–Crafts alkylation of benzene with cyclohexyl chloride using a catalyst such as aluminum trichloride: [2] C 6 H 6 + C 6 H 11 Cl → C 6 H 5 −C 6 H 11 + HCl. Cyclohexylbenzene is now industrially produced by the acid-catalyzed alkylation of benzene with cyclohexene. [3] [4] The process can proceed using benzene as the ...
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.
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)
These reactions primarily form cyclopentenones, a cycloalkene that contains two functional groups: the cyclopentene and a ketone group. [12] However, other cycloalkenes, such as Cyclooctatetraene, can be formed as a result of this reaction. [11] Formation of a cyclohexane from a non-cyclic compound via a Cyclization Reaction