Cyclo hexanol

In preparing cyclohexene by the dehydration of cyclo-hexanol with sulfuric acid (Org. Syn. Coll. Vol. i, 177) the time can be shortened to about two hours by boiling the mixture in a round-bottomed flask provided with a reflux condenser with water maintained at about 75°. A tube at the top leads to a downward cold-water condenser. 

Oxidation of tim5-4-(2,2,2-tnfluoro-l-hydroxy 1 tnfluoromethylethyl)cyclo-hexanol with pyridinium chlorochromate results m the correspondmg cyclic ketone whereas oxidation with nitnc acid m the presence of a catalyst causes ring cleavage [50] (equation 46)... 

Continuous porous polymer rods have been prepared by an in situ polymerization within the confines of a chromatographic column. The column is filled with glycidyl methacrylate and ethylene dimethacrylate monomer mixtures, cyclo-hexanol and dodecanol diluents, and AIBN initiator. They are then purged with nitrogen, stopped, and closed with a silicon rubber septum. The polymerization is allowed to proceed for 6 hr at 70°C with the column acting as a mold (47). 

Cyclohexanol, 4-rerr-butyl-, as- [Cyclo-hexanol, 4-(l,l-dimethylethyl)-, cis-], 99... 

In geteilter Zelle und 2 n Schwefelsaure laBt sich Phenol an Platin-Kathoden zu Cyclo-hexanol hydrieren (niedrige Stromdichte 56% d.Th.)6,7. Analog reagieren Methyl-phe-nole, -aniline und -benzoesauren sowie Methoxy-toluole usw.7. 1-Naphthol wird zu 7-Hydroxy-dekalin und 2-Naphthol zu 6-Hydroxy-tetralin in mittleren Ausbeuten reduziert7. 

When methanol was used to rinse a pestle and mortar which had been used to grind coarse chromium trioxide, immediate ignition occurred due to vigorous oxidation of the solvent. The same occurred with ethanol, 2-propanol, butanol and cyclo-hexanol. Water is a suitable cleaning agent for the trioxide [1]. For oxidation of sec-alcohols in DMF, the oxide must be finely divided, as lumps cause violent local reaction on addition to the solution [2]. Use of methanol to reduce the Cr(VI) oxide to a Cr(III) derivative led to an explosion and fire [3], The ignitability of the butanols decreases from n -through sec- to iert-butanol [4],... 

Interaction with a range of alcohols (n-propanol to n-octanol, benzyl alcohol, cyclo-hexanol) to form the alkoxides usually led to explosions unless air in the containing vessel was displaced by nitrogen before addition of potassium in small portions with stirring. 

Ein Beispiel fur die TiFFENEAU-Umlagerung ist die Ringerweiterung von 1 -Aminomethyl-cycloalkanolen durch Einwirkung von salpetriger Saure zu cyclischen Ketonen. Nach Versuchen von Arnold (6) mit 1 -Aminomethyl- [14C]-cyclo-pentanol-1 lmd - -Aminomethyl-[14C]-cyclo-hexanol-1 erscheint nach der Umlagerung das markierte Atom in der 2-Stellung des Ketons. 

The question about the competition between the homolytic and heterolytic catalytic decompositions of ROOH is strongly associated with the products of this decomposition. This can be exemplified by cyclohexyl hydroperoxide, whose decomposition affords cyclo-hexanol and cyclohexanone [5,6]. When decomposition is catalyzed by cobalt salts, cyclohex-anol prevails among the products ([alcohol] [ketone] > 1) because only homolysis of ROOH occurs under the action of the cobalt ions to form RO and R02 the first of them are mainly transformed into alcohol (in the reactions with RH and Co2+), and the second radicals are transformed into alcohol and ketone (ratio 1 1) due to the disproportionation (see Chapter 2). Heterolytic decomposition predominates in catalysis by chromium stearate (see above), and ketone prevails among the decomposition products (ratio [ketone] [alcohol] = 6 in the catalytic oxidation of cyclohexane at 393 K [81]). These ions, which can exist in more than two different oxidation states (chromium, vanadium, molybdenum), are prone to the heterolytic decomposition of ROOH, and this seems to be mutually related. 

In reactions carried out for 24 h at room temperature, a 95% yield of cyclo-hexanol from cyclohexanone was obtained. Other ketones and aldehydes were also hydrogenated under identical conditions, but with slower rates (38% conversion for hydrogenation of 2-hexanone, 25% conversion of acetophenone, 45% for 3-methyl-2-butanone). Insertion of the C=0 bond of the ketone or aldehyde into the Cr-H bond was proposed as the first step, producing a chromium alk-oxide complex that reacts with acid to generate the alcohol product. The anionic chromium hydride [(COJsCrH]- is regenerated from the formate complex by... 

P. Ramalah, R. Krishnamurti, and G. K. S. Prakash 232 1 -TRIFLUOROMETHYL-1 -CYCLO-HEXANOL... 

Several catalytic test reactions have been used for indirect characterization of acid and base properties of solids (78). Among them, decomposition of alcohols such as 2-propanol (79,80), 2-methyl-3-butyn-2-ol (81,82), 2-methyl-2-butanol (83), cyclo-hexanol (84), phenyl ethanol (55), and t-butyl alcohol (86) have been investigated. In... 

One of the best known explosion disasters took place in Flixborough, England, in 1974. Nypro Limited manufactured 70,000 tons/year of caprolactam as intermediate for the manufacturing of nylon. This is done by air oxidation of cyclohexane to cyclo-hexanol, with the help of a number of catalysts in the reactors. At that time, cracks developed in the reactor combined with pipe rupture, which released 30 tons of cyclohexane in a cloud. It was ignited by an unknown source and exploded, which resulted in 28 deaths and 36 injured, and the fire burned for 10 days. This disaster was also devastating to the future of the company. 

Fig. 16. Plots of P 8) 112 versus sin2 (6/2) for a PBLGsample Nw = 2590) in a DCA-cyclo-hexanol mixture (8.3 wt.- % CHL) and in DMF (49). N denotes the wight-average degree...

In a side-reaction 10-15% carboxylic acids are produced by oxidative cleavage of the ketone enolates. The cleavage is favoured by higher temperatures e.g. cyclo-hexanol leads to 80% cyclohexanone and 16% adipic acid at 25 °C, whilst at 80 °C 5% ketone and 42% diacid are found. These acidic by-products are easily separated, since they remain in the alkaline solution during workup. The oxidation of 6 gave the acetal 7 as main product (28%) together with 4% of the ketone 8 and 56% of unchanged 6. The acetal 7 is probably formed by nucleophilic addition of the alcohol 6 at the activated triple bond of ketone 8. 

Fraction 2 showed the same retention time as that of authentic cyclo-hexanol, and its infrared spectrum showed a strong absorption band at 3350 cm."1 (—OH). The a-naphthylurethane derivative was prepared, and a mixed melting point with an authentic sample was not depressed, m.p., 128°-129°C. [literature value, 128°C. (17)]. 

Autoxidation without Discharge. To compare our results with normal autoxidation, the reaction was carried out using a reaction mixture similar to Run 4 without silent discharge. Low conversion of cyclohexene (0.051% ) was observed at 60°C., indicating that the discharge oxidation was hardly affected by the normal autoxidation process under the present reaction conditions. The major product was 3-cyclohexenylhydroperoxide, and minor products were 3-cyclohexenol, 3-cyclohexenone, cyclohexene oxide, and trace amounts of residue saturated materials such as cyclo-hexanol and cyclohexanone were not detected. The conversion of cyclohexene was raised to 0.15% when the reaction temperature was elevated to 140°C. however, the kinds of product were not changed. 

Fig. 5.4. Ratio of Maxwell-constant to intrinsic viscosity as a function of molecular weight for linear oligomers of poly oxy-propylene glycol in cyclo-hexanol at 20° C (full circles). Ratio of birefringence to shear stress in the limit of zero shear stress for the same oligomers in bulk (temperatures 20—60° C) (open squares). The experimental point at the righthand side is obtained on a high molecular weight sample, Tsvetkov, Garmonova and Stankevich (166)...

Cydohexanol or Hexahydrophenol (called Cyclo-hexanol or Hexahydrophenol in Ger),... 

The following solvents are now manufactured on the large scale for industrial purposes ethylene dichloride, di-, tri-, and tetra-chloroethy-lene, tetrachloroethane, dichloroethyl ether, hexahydrobenzene, cyclo-hexanol, tetra- and deca-hydronaphthalene (tetralin and dekalin), triacetin, ethylene glycol, butyl alcohol, diacetone alcohol, ethyl lactate, isopropyl ether, etc. 

Adachi, K., Suga, H. and Seki, S. Phase changes in crystalline and glassy-crystalline cyclo-hexanol. Bull. Chem. Soc. Japan 41, 1073 (1968)... 

Optical resolution of some hydrocarbonds and halogeno compounds by inclusion complexation with the chiral host (9a) has been accomplished.11,12 Preparation of optically active hydrocarbons is not easy and only a few example of the preparation of optically active hydrocarbons have been reported. For example, optically active 3-phenylcyclohexene has been derived from tartaric acid through eight synthetic steps.11 Although one-step synthesis of optically active 3-methylcyclohexene from 2-cyclo- hexanol by the Grignard reaction using chiral nickel complex as a catalyst has been reported, the enantiomeric purity of the product is low, 15.9%.11 In this section, much more fruitful results by our inclusion method are shown. 

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