Search results
Results from the WOW.Com Content Network
The Beckmann Rearrangement. The archetypal Beckmann rearrangement [4] is the conversion of cyclohexanone to caprolactam via the oxime. Caprolactam is the feedstock in the production of Nylon 6. [5] The Beckmann solution consists of acetic acid, hydrochloric acid and acetic anhydride, and was widely used to
The most famous and commercially important reaction of cyclohexanone oxime is Beckmann rearrangement yielding ε-caprolactam, which is used to produce Nylon 6: This reaction is catalyzed by sulfuric acid, [1] but industrial scale reactions use solid acids. [2] Typical of oximes, the compound can be reduced by sodium amalgam to produce ...
It was estimated that 90% of all caprolactam is synthesised from cyclohexanone (1), which is first converted to its oxime (2). Treatment of this oxime with acid induces the Beckmann rearrangement to give caprolactam (3): [2] The immediate product of the acid-induced rearrangement is the bisulfate salt of caprolactam.
About half of the world's supply of cyclohexanone, more than a million tonnes annually, is converted to the oxime. In the presence of sulfuric acid catalyst , the oxime undergoes the Beckmann rearrangement to give the cyclic amide caprolactam: [ 18 ]
Conversion of cyclohexanone to caprolactam involving the Beckmann rearrangement. Approximately 95% of hydroxylamine is used in the synthesis of cyclohexanone oxime, a precursor to Nylon 6. [10] The treatment of this oxime with acid induces the Beckmann rearrangement to give caprolactam (3). [21]
The use of N-hydroxyphthalimide as a catalyst in the oxidation of KA oil avoids the formation of the undesirable by-product ammonium sulfate which is produced by the conventional ε-caprolactam synthesis (Beckmann rearrangement of cyclohexanone oxime with sulfuric acid). Alkanes are converted into nitroalkanes in the presence of nitrogen ...
Examples include high impact applications of the Beckmann rearrangement (for introduction of nitrogen into codeine) [14] and the Baeyer-Villiger oxidation (introduction of oxygen to cage-annulated ethers) [15] in synthesis. Both occur with the expulsion of a leaving group as the alkyl group migrates onto the exocyclic heteroatom, which is ...
After a short synthesis to obtain the desired spiro-[5.4] system, Nobel laureaute E.J. Corey and co-workers employed a Barton reaction to selectively introduce an oxime in a 1,3-diaxial position to the nitrite ester. The oxime is converted to a lactam via a Beckmann rearrangement and then reduced to the natural product. [24]