Cyclohexanones catalytic

H2N (CH2)a NH2- Colourless solid when pure m.p. 4LC, b.p. 204 C. Manufactured by the electrochemical combination of two molecules of acrylonitrile to adiponitrile followed by catalytic reduction, or by a series of steps from cyclohexanone via adipic acid. Used in the production of Nylon [6, 6]. 

Allied-Signal Process. Cyclohexanone [108-94-1] is produced in 98% yield at 95% conversion by liquid-phase catal57tic hydrogenation of phenol. Hydroxylamine sulfate is produced in aqueous solution by the conventional Raschig process, wherein NO from the catalytic air oxidation of ammonia is absorbed in ammonium carbonate solution as ammonium nitrite (eq. 1). The latter is reduced with sulfur dioxide to hydroxylamine disulfonate (eq. 2), which is hydrolyzed to acidic hydroxylamine sulfate solution (eq. 3). 

BASF. In the Badische process, cyclohexanone is produced by Hquid-phase catalytic air oxidation of cyclohexane to KA oil, which is a mixture of cyclohexanone and cyclohexanol, and is followed by vapor-phase catalytic dehydrogenation of the cyclohexanol in the mixture. Overall yields range from 75% at 10% cyclohexane conversion to 80% at 5% cyclohexane conversion. 

Dutch State Mines (Stamicarbon). Vapor-phase, catalytic hydrogenation of phenol to cyclohexanone over palladium on alumina, Hcensed by Stamicarbon, the engineering subsidiary of DSM, gives a 95% yield at high conversion plus an additional 3% by dehydrogenation of coproduct cyclohexanol over a copper catalyst. Cyclohexane oxidation, an alternative route to cyclohexanone, is used in the United States and in Asia by DSM. A cyclohexane vapor-cloud explosion occurred in 1975 at a co-owned DSM plant in Flixborough, UK (12) the plant was rebuilt but later closed. In addition to the conventional Raschig process for hydroxylamine, DSM has developed a hydroxylamine phosphate—oxime (HPO) process for cyclohexanone oxime no by-product ammonium sulfate is produced. Catalytic ammonia oxidation is followed by absorption of NO in a buffered aqueous phosphoric acid... 

Cyclohexanone [108-94-17 is a colorless, mobile Hquid with an odor suggestive of peppermint and acetone. Cyclohexanone is used chiefly as a chemical iatermediate and as a solvent for resias, lacquers, dyes, and iasecticides. Cyclohexanone was first prepared by the dry distillation of calcium pimelate [19455-79-9] OOC(CH2 )5COO Ca , and later by Bouveault by the catalytic dehydrogenation of cyclohexanol. 

Other methods for the preparation of cyclohexanecarboxaldehyde include the catalytic hydrogenation of 3-cyclohexene-1-carboxaldehyde, available from the Diels-Alder reaction of butadiene and acrolein, the reduction of cyclohexanecarbonyl chloride by lithium tri-tcrt-butoxy-aluminum hydride,the reduction of iV,A -dimethylcyclohexane-carboxamide with lithium diethoxyaluminum hydride, and the oxidation of the methane-sulfonate of cyclohexylmethanol with dimethyl sulfoxide. The hydrolysis, with simultaneous decarboxylation and rearrangement, of glycidic esters derived from cyclohexanone gives cyclohexanecarboxaldehyde. 

A route to phenol has been developed starting from cyclohexane, which is first oxidised to a mixture of cyclohexanol and cyclohexanone. In one process the oxidation is carried out in the liquid phase using cobalt naphthenate as catalyst. The cyclohexanone present may be converted to cyclohexanol, in this case the desired intermediate, by catalytic hydrogenation. The cyclohexanol is converted to phenol by a catalytic process using selenium or with palladium on charcoal. The hydrogen produced in this process may be used in the conversion of cyclohexanone to cyclohexanol. It also may be used in the conversion of benzene to cyclohexane in processes where benzene is used as the precursor of the cyclohexane. 

Tetrahydrocarboline derivatives have recently been synthesized from 2-o-nitroarylated cyclohexanone derivatives. Thus, reductive cyclization of 3-(2,4-dinitrophenyl)-l-methyl-4-piperidone (68) (prepared by the reaction of 2,4-dinitrochlorobenzene with l-methyl-4-A-pyrrolidmo-3-piperideine) gave 7-amino-2-methyl-l,2,3,4-tetrahydro-y-carboline (69). Neither catalytic nor chemical reduction of the... 

Propose a structure for the product with fonnula C9H17N that results when 2-(2-cyanoethyl)cyclohexanone is reduced catalytically. 

The conjugate addition of Grignard reagents to 2-cyclohexenone was promoted by catalytic amounts (2-4 mol %) of alkylcopper(I) complexes of the lithium amide prepared from N- (R)-1 -phenylethyl]-2-[(/ )-l-phenylethyliminojcycloheptatrienamine, Li[CuR(CHIRAMT)]52,11. However, 3-substituted cyclohexanones were obtained in very low ee (4-14%). 

A further extension of the MIMIRC reaction is seen in the synthesis of enantiomerically pure cyclohexanones. A successful diastereoselective MIMIRC reaction with 2-(rer/-butyldimethylsi-lyloxy)-4-phenyl-l,3-butadiene and an optically pure (Z)-y-alkoxy-substituted enone was performed using catalytic amounts (5 mol%) of triphenylmethyl perchlorate at — 78 ,C 360,408 (for a further example see Section 1.5.2.4.4.1.). 

Because the trimethylsilyl enol ether of cyclohexanone 107 a is considerably more bulky than the corresponding dimethylsilyl enolate 107b, only the latter reacts with the N-tosyhmine 108 in the presence of catalytic amounts of diisopropylamine in DMF/H2O at 78°C or at room temperature to give the Mannich type compounds 109 in high yields [39] (Scheme 3.4). 

New materials are also finding application in the area of catalysis reiated to the Chemicals industry. For example, microporous [10] materials which have titanium incorporated into the framework structure (e.g. so-calied TS-1) show selective oxidation behaviour with aqueous hydrogen peroxide as oxidizing agent (Figure 5). Two processes based on these new catalytic materials have now been developed and commercialized by ENl. These include the selective oxidation of phenol to catechol and hydroquinone and the ammoxidation of cyclohexanone to e-caproiactam. 

Diynes 60 react with aldehydes 61 in the presence of [ (CODj l/SIPr catalytic system to afford dienones 63 upon electrolytic ring opening of the expected pyrans 62 (Scheme 5.18) [20]. When cyclohexanone 64 is employed the pyran ring 65 is obtained in good yield. 

The role of oxygen on the allyhc oxidation of cyclohexene over the FePcCli6-S/TBHP catalytic system was determined by using 2 labelled oxygen. Since more than 70% of the main cyclohexene oxidation products, 4,11, and 12, had labelled oxygen, we can assure that molecular oxygen acts as co-oxidant. However, under the reaction conditions the over-oxidation of 4 seems to be unavoidable. Labelled 2, 3- epoxy-l-cyclohexanone (13), 2-cyclohexen-l, 4-dione (14), and 4-hydroxy-2-cyclohexen-l-one (15) were detected as reaction products. 

We recently reported that Cu/Si02 is an effective catalyst for the hydrogenation of cyclohexanones under very mild experimental conditions. Thus, a series of cyclohexanones with different substituents, including 3-oxo-steroids, could be reduced under 1 atm of H2 at 40-90°C, with excellent selectivity (5). The catalyst is non-toxic and reusable. This prompted us to investigate the reduction of cyclohexanones over a series of supported copper catalysts under hydrogen transfer (h.t.) conditions (2-propanol, N2, 83 °C) and to compare the results with those obtained under catalytic hydrogenation (n-heptane, 1 atm H2, 40-90°C) conditions. Here we report the results obtained in the hydrogenation of 4-tert-butyl-cyclohexanone, a molecule whose reduction,... 

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. 

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