Cyclohexanone with phenol

The reaction product was filtered to remove catalyst and analyzed in GC equipped with an HP5 (30 m X 0.32 mm X 0.25 pm) column. The temperature program used for analysis (31 °C - 35 min - 1 °C/min - 40 °C - 10 °C/min -120 °C) ensured complete separation of the cyclohexanol, cyclohexanone, and phenol peaks. The conversion and selectivity were calculated directly from the area of each peak. 

The production of Cyclohexanone from phenol was simplified when selective hydrogenation with Pd catalysts was made possible ([see Eq. 21.3)]. In this process, phenol is completely converted in the gas phase at 140 to 170°C and 1 to 2 bar using a supported Pd catalyst containing alkaline earth oxides (e.g., Pd-CaO/A Os). The selectivity to Cyclohexanone is greater than 95%46. 

Dialkylphenols. These phenols are obtained by a cross-aromatization of cyclohexanones with aldehydes catalyzed by this zirconium complex. Cp2TiCl2 and Cp2HfCl2 are also effective catalysts.1... 

The separation section receives liquid streams from both reactors. For assessment the residue curve map in Figure 5.7 is of help. The first separation step is the removal of lights. This operation can take place in a distillation column operated under vacuum (200mmHg) with a partial condenser. Next, the separation of the ternary mixture cyclohexanone/cyclohexanol/phenol follows. Two columns are necessary. In a direct sequence (Figure 5.15) both cyclohexanone and cyclohexanol are separated as top products. The azeotrope phenol/cyclohexanol to be recycled is the bottoms from the second split In an indirect sequence (Figure 5.16) the azeotropic phenol mixture is a bottom product already from the first split. Then, in the second split cyclohexanone is obtained as the top distillate, while cyclohexanol is taken off as the bottom product The final column separates the phenol from the heavies. 

A liquid mixture of cyclohexanone(l)/phenol(2) for which x, = 0.6 is in equilibrium with its vapor at 144°C. Determine the equilibrium pressure P and vapor composition y, from the following information ... 

Kvaerner Process Technology Cyclohexanone/cydohexanol Phenol/hydrogen Synthesis of KA oil with high selectivity to cyclohexanone 2 1998... 

Dehydrogenation of cyclohexanol with formation of cyclohexanone and phenol Pd-25 Ag 625 57... 

It was found originally by Swift and Bozik in an early study of supported bimetallic catalysts that the addition of tin to a nickel-silica catalyst greatly promoted the activity and gave a longer catalyst life for the dehydrogenation of cyclohexanol or cyclohexanone to phenol, especially with a... 

In the palladium(0)-catalyzed reaction of (l-methylethylidene)cyclopropane (1, R = Me) with cycloalk-2-enones, mixtures of isomers with respect to the stereochemistry of the ring fusion are formed, the preferences being dependent on the ring size of the cycloalkenone. Analogous reactions with (diphenylmethylene)cyclopropane (1, R = Ph) lead to improved product yields but decreased stereoselectivity. In the case of cyclohex-2-enone (n = 3), palladium(0)-catalyzed disproportionation of the enone to yield cyclohexanone and phenol may also occur. With (diphenylmethylene)cyclopropane, this side reaction is of minor importance because of the high tendency of this substrate to undergo cycloaddition. However, with 2-methylene-l,l-diphenylcyclopropane as substrate, the disproportionation reaction predominates. " " ... 

The commercial development of PPO started in the 1960s, and the first priority was to find an efficient and low-cost procedure to produce the monomer, namely, DMP. Thus, DMP is obtained from cyclohexanone hence, the reaction of cyclohexanone with formaldehyde at 350 °C in the presence of tricalcium phosphate generates DMP with a reasonable yield [33]. DMP can also be produced by the reaction of phenol with methanol at 350 °C, with magnesium oxide as catalyst [34]. The latter method rendered the manufacture of the polymer economically attractive accordingly, from 1964, its commerciaUzation accelerated. 

Carbonyl Compounds. In the case of aldehydes, only self-condensation products are obtained, whereas aliphatic ketones usually form the corresponding dithiocarboxylates or a-ketoketene dithioacetals. If cyclic ketones are used, occurrence of carbon-carbon cleavage or formation of a-ketoketene acetals depend on the steric demands of the base. Treatment of cyclohexanone with lithium 4-methyl-2,6-di-f-butylphenoxide (12) (readily obtained by treatment of the phenol with n-butyllithium) and CS2, followed by methylation, leads via the dithiocarboxylate ion (13) to the a-ketoketene dithioacetal (14) (eq 10). ... 

The vibrational spectrum and normal co-ordinate analysis of cyclopropenone and its dideuterio-derivative have revealed that the carbon-carbon double-bond stretch occurs at the remarkably low wavenumber of 1483 cm" (1403 cm" in the dideuterio-compound). The authors have concluded that the bands at 1650 and 1850 cmin disubstituted analogues are an in-phase and out-of-phase mixture, respectively, of approximately equal amounts of the C=0 and C=C components conflicting with this is the observation that only the band at 1650cm is shifted to lower wavenumber ( 1620cm" ) on complexation with phenol in carbon tetrachloride. These latter studies have established the order of basicities of a series of cyclic polyenones relative to cyclohexanone in a non-co-ordinating solvent. 

In 2009, Fu et al. developed highly 4-phenoxy-substituted prolinamide phenols, which could promote the asymmetric aldolisation of cyclohexanone with a range of aldehydes with a high degree of diastereo- and enantioselectivity in a large amount of water (Scheme 2.12). The best enantioselectivities of up to 97% ee were obtained with the most steric hindered catalyst that bore a tert-butyl group on the phenol moiety. The scope of the reaction could be extended to aliphatic ketones with enantioselectivities of up to 94% ee, albeit with low to moderate diastereoselectivities of up to 50% de. 

Scheme 2.12 Aldolisations of cyclohexanone with aldehydes catalysed by 4-phenoxy prolinamide phenol.

As an example, the joint analysis of IR and Raman spectra provided evidence of the partial ordering of cations in a Fe-Cr corundum-type mixed sesquioxides, which are used industrially as high temperature water-gas shift catalysts, but are also active in olefin oxidative dehydrogenation. X-ray diffraction (XRD) patterns of these solids indicate the conmdum-type structure without any superstructure. This implies that iron and chromium ions are randomly distributed. IR and Raman spectra instead definitely show that cations are at least partially ordered in layers such as in the ilmenite-type superstructure. Similarly, XRD analysis shows a cubic (non-ferroelectric) structure of nanometric BaTi03, while vibrational spectroscopies reveal microscopic asymmetry of this structure. Similarly, IR spectroscopy allowed the determination of the state of vanadium in solid solution in Ti02 anatase catalysts, and the presence of Ti" + in the silicalite framework of TSl catalysts, " used for the selective oxidation of phenol and the ammoximation of cyclohexanone with hydrogen peroxide. 

During the last period considerable attention has been given to Ti-silicalite, a zeolite derived from silicalite by partial substitution of framework Si with Ti (refs. 1-3). This zeolite exhibits very valuable catalytic properties for a variety of reactions of industrial interest, in particular for cyclohexanone ammoximation, phenol hydroxilation and olefins epoxidation (refs. 4, 5). Despite that, the stability of Ti-silicalite, as well as fundamental aspects of its characteristics and catalytic behaviour, has not been studied. In this work sorption measurements of small (N ) and large (p- and m-xylene) probe molecules were performed to characterize the porous structure of Ti-silicalite, before and after various thermal treatments. The results, compared to those obtained by spectroscopic and diffractometric techniques, provided information on stability of both zeolite lattice and titanium inserted in the framework. 

Excellent synergy effect of Pd/C with solid Lewis acids exists in the hydrogenation of phenol to cyclohexanone with almost 100% selectivity under mild conditions. CO2 could enhance the apparent reaction rate, and the phase behavior influenced... 

C, b.p. 16UC. Manufactured by heating phenol with hydrogen under pressure in the presence of suitable catalysts. Oxidized to adipic acid (main use as intermediate for nylon production) dehydrogenated to cyclohexanone. 

Phenol Vi Cyclohexene. In 1989 Mitsui Petrochemicals developed a process in which phenol was produced from cyclohexene. In this process, benzene is partially hydrogenated to cyclohexene in the presence of water and a mthenium-containing catalyst. The cyclohexene then reacts with water to form cyclohexanol or oxygen to form cyclohexanone. The cyclohexanol or cyclohexanone is then dehydrogenated to phenol. No phenol plants have been built employing this process. 

A Methylamino)phenol. This derivative, also named 4-hydroxy-/V-methy1ani1ine (19), forms needles from benzene which are slightly soluble in ethanol andinsoluble in diethyl ether. Industrial synthesis involves decarboxylation of A/-(4-hydroxyphenyl)glycine [122-87-2] at elevated temperature in such solvents as chlorobenzene—cyclohexanone (184,185). It also can be prepared by the methylation of 4-aminophenol, or from methylamiae [74-89-5] by heating with 4-chlorophenol [106-48-9] and copper sulfate at 135°C in aqueous solution, or with hydroquinone [123-31 -9] 2l. 200—250°C in alcohoHc solution (186). 

Caprolactam [105-60-2] (2-oxohexamethyleiiiiriiQe, liexaliydro-2J -a2epin-2-one) is one of the most widely used chemical intermediates. However, almost all of the aimual production of 3.0 x 10 t is consumed as the monomer for nylon-6 fibers and plastics (see Fibers survey Polyamides, plastics). Cyclohexanone, which is the most common organic precursor of caprolactam, is made from benzene by either phenol hydrogenation or cyclohexane oxidation (see Cyclohexanoland cyclohexanone). Reaction with ammonia-derived hydroxjlamine forms cyclohexanone oxime, which undergoes molecular rearrangement to the seven-membered ring S-caprolactam. 

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). 

The oxidation of cyclohexane to a mixture of cyclohexanol and cyclohexanone, known as KA-od (ketone—alcohol, cyclohexanone—cyclohexanol cmde mixture), is used for most production (1). The earlier technology that used an oxidation catalyst such as cobalt naphthenate at 180—250°C at low conversions (2) has been improved. Cyclohexanol can be obtained through a boric acid-catalyzed cyclohexane oxidation at 140—180°C with up to 10% conversion (3). Unreacted cyclohexane is recycled and the product mixture is separated by vacuum distillation. The hydrogenation of phenol to a mixture of cyclohexanol and cyclohexanone is usually carried out at elevated temperatures and pressure ia either the Hquid (4) or ia the vapor phase (5) catalyzed by nickel. 

Cyclohexanone purity is most readily deteanined by gas-Hquid chromatography over DC-710 or carbowax 20M-on-chromosorb. Impurities such as cyclohexane, ben2ene, cyclohexanol, and phenol do not interfere. In the absence of other carbonyl compounds cyclohexanone may be deterrnined by treatment with hydroxylamine hydrochloride, which forms the oxime, as follows ... 

Christopher and Fox have given examples of the way in which polycarbonate resins may be tailor-made to suit specific requirements. Whereas the bis-phenol from o-cresol and acetone (bis-phenol C) yields a polymer of high hydrolytic stability and low transition temperature, the polymer from phenol and cyclohexanone has average hydrolytic stability but a high heat distortion temperature. By using a condensate of o-cresol and cyclohexanone a polymer may be obtained with both hydrolytic stability and a high heat distortion temperature. 

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. 

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