Of cyclohexanone oxime

SEMMLER WOLFF SCHROETER OximeAromatizatlon Aramatization of cyclohexanone oximes to anilines... 

Reaction of hydroxylamine-0-sulfonic acid with cyclohexanone in alkaline solution can be shown to give pentamethyleneoxazirane (16). Compound 16 is an isomer of cyclohexanone oxime. It decomposes even at room temperature and thus cannot be prepared in a pure state. 

Sticking with nylon production, high-silica pentasil zeolites are used by Sumitomo to overcome environmental issues associated with the conversion of cyclohexanone oxime to caprolactam (Chapter 1, Scheme 1.4). 

The TS-1 catalysed ammoximation of cyclohexanone with NH3/H2O2 is a new process (Romano et ai, 1990) for the production of cyclohexanone oxime, the precursor of caprolactam. In the existing process, the oxime is produced by reaction of cyclohexanone... 

Fe3+, La3+ and Ce3+ ion-exchanged MAPO-36 was prepared by wet ion-exchange method. The materials were characterized by XRD, TGA and TPD (ammonia). Lewis acid metal ions are suggested to remain as charge compensating MO+ species after calcination in ion-exchanged MAPO-36. Beckmann rearrangement of cyclohexanone oxime was studied over these catalysts in the vapour phase. 

Beckmann rearrangement of oxime is an acid catalysed reaction. The environmental problems associated with the use of sulphuric acid instigated interest to use number of solid acid catalysts [1], There are only scanty references about Lewis acid ion-exchanged MeAlPOs. Beyer et al. [2], Mihalyi et al. [3] and Mavrodinova et al. [4] already suggested the presence of Lewis acid metal ions as MO+ species in zeolites. The present study focussed the synthesis and characterisation of Fe3+, La3+ and Ce3+ ion-exchanged MAPO-36. The catalytic results of Beckmann rearrangement of cyclohexanone oxime over ion-exchanged catalysts are delineated in this article. 

Zeolites have also been described as efficient catalysts for acylation,11 for the preparation of acetals,12 and proved to be useful for acetal hydrolysis13 or intramolecular lactonization of hydroxyalkanoic acids,14 to name a few examples of their application. A number of isomerizations and skeletal rearrangements promoted by these porous materials have also been reported. From these, we can underline two important industrial processes such as the isomerization of xylenes,2 and the Beckmann rearrangement of cyclohexanone oxime to e-caprolactam,15 which is an intermediate for polyamide manufacture. Other applications include the conversion of n-butane to isobutane,16 Fries rearrangement of phenyl esters,17 or the rearrangement of epoxides to carbonyl compounds.18... 

The transformation of oximes to lactams (the Beckmann rearrangement) was one of the earliest such acid-catalyzed reactions to be reported with TS-1 (138) and TS-2 (247) catalysts. The rearrangement of cyclohexanone oxime to e-caprolactam proceeds with high selectivity in the presence of TS-1, with high catalyst stability (138,247). 

Scheme 7.9 Hydrolysis of cyclohexanone oxime to hydroxylamine with nitric oxide formation.

D. Parmar, L. T. Burka, Metabolism and Disposition of Cyclohexanone Oxime in Male F-344 Rats , Drug Metab. Dispos. 1991, 19, 1101 - 1107. 

Reduction of cyclohexanone oxime with lithium aluminum hydride in tetra-hydrofuran gave cyclohexylamine in 71% yield [809], and reduction of ketoximes with sodium in methanol and liquid ammonia [945] or in boiling ethanol [946] afforded alkyl amines, usually in good to high yields. Stannous chloride in hydrochloric acid at 60° reduced the dioxime of 9,10-phenanthra-... 

Whereas diborane in tetrahydrofuran reduces oximes only at 105-110 , oxime ethers and oxime esters are reduced to amines and alcohols at room temperature in good yields. For example the p-nitrobenzoyl ester of cyclohexanone oxime gave a 67% yield of cyclohexylamine and 81% yield of p-nitrobenzyl alcohol [948]. 

The student should adapt this general mechanism and work through the specific cyclic example of cyclohexanone oxime to caprolactam. Note that the result of the shift is an expansion of the ring size in the final amide product with the incorporation of the nitrogen atom as part of the ring. 

Caprolactam is discussed more completely in Chapter 11, Section 5. It is made from cyclohexane by oxidation to cyclohexanone-cyclohexanol mixture, formation of cyclohexanone oxime, and acid-catalyzed rearrangement. 

Pyrrolidone is a lactone used for the production of nylon-4. This reactant may be produced by the reduction ammoniation of maleic anhydride. s-Caprolactam, used in the production of nylon-6, may be produced by the Beckman rearrangement of cyclohexanone oxime (structure 17.11). The oxime may be produced by the catalytic hydrogenation of nitrobenzene, the photolytic nitrosylation of cyclohexane (structure 17.9), or the reaction of cyclohexanone and hydroxylamine (structure 17.10). Nearly one-half of the production of caprolactam is derived from phenol. 

Organoaluminum-promoted Beckmann rearrangement/methylation of cyclohexanone oxime mesylate, followed by allylation of ketimine 40a and Mannich cyclization of the intermediate iminium-allylsilane, provides piperidine 40b possessing cxo-unsaturation (08BKC1669). 

Reaction of cyclohexanone oxime (59) with phenylacetylene in the presence of KOH/ DMSO afforded Z-[l-(2-phenylvinyl)]-3-phenyl-4,5,6,7-tetrahydroindole (60) (equation 25) °. Transformation of 0-vinylacetophenone oxime (61) in the system f-BuOK/THF has been studied. The reaction at 60-65 °C afforded 2,4-diphenylpyrrole (62) and oligomeric products instead of the desired 2-phenylpyrrole (equation 26) . ... 

The Beckmann rearrangement of cyclohexanone oxime catalysed by solid metaboric acid (286) has also been investigated (equation 94). When ketoximes, mixed with 286 (formed from boric acid at 100°C/0.1 Torr), are heated (140°C/7-42 h) the corresponding amides or lactams are produced in excellent yields (62-92%). Under the... 

To explain the difficulties encountered in the reuse of sulfonyl chloride functionalized ionic liquids during Beckmann rearrangement, Deng and colleagues proposed a mechanism for rearrangement of cyclohexanone oxime (equation 97). 

There is extensive research ongoing for new synthesis processes which are economically favourable due to less expensive reactants or easier processes. One very important point is the avoidance of the production of a large amount of ammonium sulfate, which can be achieved by the prevention of the formation of any salt or by the replacement of ammonium sulfate by another ammonium salt with increased economical value. Recently, studies of Beckmann rearrangement of cyclohexanone oxime in friendly enviionment conditions have received special attention . ... 

The reactor systems were also improved, concerning the Beckmann rearrangement of cyclohexanone oxime and the production of the unwanted ammonium salts ", by-products and contaminants" ". 

Recently, the Sumitomo Chemical Co., Ltd. developed the vapour-phase Beckmann rearrangement process for the production of 8-caprolactam. In the process, cyclohexanone oxime is rearranged to e-caprolactam by using a zeolite as a catalyst instead of sulfuric acid. EniChem in Italy developed the ammoximation process that involves the direct production of cyclohexanone oxime without producing any ammonium sulfate. The Sumitomo Chemical Co., Ltd. commercialized the combined process of vapour-phase Beckmann rearrangement and ammoximation in 2003 ". 

A. Cyatohexanone oxime methanesulfonate. A dry, 1-L, two-necked, round-bottomed flask is equipped with a gas inlet, rubber septum, and magnetic stirring bar. The flask is charged with 17.0 g (0.15 mol) of cyclohexanone oxime (Note 1) and flushed with argon, after which 300 mL of dichloromethane followed by 25 mL (0.18 mol) of triethylamine (Note 2) are injected through the septum into the flask. The solution is stirred and cooled to a temperature of -15 to -20°C in a dry ice-carbon tetrachloride bath, while 12.8 mL... 

HCA478). A similar route to quinolines via 1,2- dihydroquinolines starts fromN-propargyl-anilines and is copper catalyzed (62JOC4713). The allyl ether of cyclohexanone oxime (126) heated in benzene at 200 °C gives 5,6,7,8-tetrahydroquinoline (79S221) the proposed mechanism is reinforced by the isolation of a compound (128) formed from the ether (126) and a suggested intermediate (127). 

On vacuum fractional distillation of the product mixture, 1 gm of cyclohexanone oxime and 19.5 gm (85%) of crude azoxycyclohexane are isolated. 

To a vigorously stirred suspension of 54.5 gm (0.3 mole) of TV-bromosuccini-mide in 150 ml of water, cooled to 10°C with an ice bath, is rapidly added a solution consisting of 11.3 gm (0.1 mole) of cyclohexanone oxime, 25.3 gm (0.3 mole) of sodium bicarbonate, and 150 ml of water over a 15 min period, while maintaining the reaction temperature at 10°C. 

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