Ketones cyclohexanone

Pimelin-keton, n, pimelic ketone (cyclohexanone), -saure,/. pimelic acid,... 

Aldehydes and ketones react reversibly with 2 equivalents of an alcohol in the presence of an acid catalyst to yield acetals, R2C(OR )2, sometimes called ketals if derived from a ketone. Cyclohexanone, for instance, reacts with methanol in the presence of HCl to give the corresponding dimethyl acetal. 

This procedure has been patterned after the method by which the carbethoxy group is introduced into a few alicyclic ketones 6 and several cyclic ketones. Cyclohexanone has been reported to yield 50% of 2-carbethoxycyclohexanone when treated with sodium hydride and diethyl carbonate using ether as the solvent.7 The preparation of 2-carbethoxycycloheptanone using potassium f-butoxide and diethyl carbonate in benzene has been reported in 40% yield.8 Jacob and Dev report an 80% yield of the latter compound using sodium hydride as the base.9... 

Addition of enantiomerically pure cnamines derived from (.Y -jmethoxymethyfipyrrolidine (SMP) and ketones (cyclohexanone, cycloheptanone, propiophenone) to AGY-dimethylmethylene-iminium tetrachloroaluminate11,42 give the corresponding Mannich bases in moderate to good yields (56 -79%) and low to moderate enantioselectivities (30-66% ce)12, l3. The (-)-isomer is the major enantiomer in each case. The absolute configuration of the major enantiomer has not been determined. The auxiliary can be recovered. 

In this study we examine the generalities in reductive alkylation however, since the subject is vast, we limited ourselves to the interaction of aromatic and aliphatic primary amines and diamines with ketones. The ketones examined include the cyclic ketone, cyclohexanone, and aliphatic ketones such as acetone, and methyl isobutyl ketone (MIBK). We limited our study to sulfided and unsulfided Pt and Pd catalysts supported on activated carbon that were commercially available from Evonik Degussa Corporation. 

For instance, 2-methylpropene reacted with acetic acid at 18°C in the presence of Al-bentonite to form the ester product (75). Ion-exchanged bentonites are also efficient catalysts for formation of ketals from aldehydes or ketones. Cyclohexanone reacted with methanol in the presence of Al-bentonite at room temperature to give 33% yield of dimethyl ketal after 30 min of reaction time. On addition of the same clay to the mixture of cyclohexanone and trimethyl orthoformate at room-temperature, the exothermic reaction caused the liquid to boil and resulted in an almost quantitative yield of the dimethyl ketal in 5 min. When Na- instead of Al-bentonite is used, the same reaction did not take place (75). Solomon and Hawthorne (37) suggest that elimination reactions may have been involved in the geochemical transformation of lipid and other organic sediments into petroleum deposits. 

TS-1 zeolites have been used in the presence of H2O2 to perform the BV reaction on cyclic and aromatic ketones . Cyclohexanone and acetophenone can be oxidized at 80 °C with selectivities lower that 60%, due to the formation of a-hydroxyketones and other undesired products. The observed modest results seem to be associated with the poor selectivity of the active Ti-peroxo species. In this respect, Corma and coworkers developed new Sn-based heterogeneous catalysts able to selectively activate the ketone instead of 11202 . Cyclic ketones are transformed into the corresponding lactones and unsaturated cyclic ketones like 110 are oxidized to unsaturated lactones in very high chemoselectivitjf , unusual for other oxidizing systems (equation 75). As expected, the authors failed to detect the presence of metal-peroxo derivatives in their systems . ... 

Keywords a,/ -unsaturated ketone, cyclohexanone, acyclic ketone, Robinson an-nulation reaction, decalenone, cyclohexenone... 

NIOSH Methods 1300 and 1301 (NIOSH 1984) describe the determination of common ketones in air. The compounds evaluated in the study include acetone, methyl propyl ketone, methyl isobutyl ketone, methyl n-butyl ketone, diisobutyl ketone, cyclohexanone, ethyl butyl ketone, methyl amyl ketone, ethyl amyl ketone, mesityl oxide, and camphor [76-22-2], The analysis involves adsorption... 

Again use Tollens reagent. Alcohols (such as benzyl alcohol) do not react. Both compounds are ketones, but 2-cyclohexenone has a carbon-carbon double bond and will be easily oxidized by potassium permanganate (the purple color of the KMn04 will turn to the brown color of Mn02). The saturated ketone, cyclohexanone, will not react. 

Similarly lV-bis(trimethylsilyl)methyltriazoles lead to the corresponding /V-bis(tri-methylsilyl)methyltriazoles with yields which are generally good to excellent, except in the case where highly enolizable ketones (cyclohexanone and (3-tetralone) are used as an electrophile. This olefination reaction is not stereoselective, except in the case of 7-phenylpropionaldehyde.71... 

Various chiral amines can catalyze the direct enantioselective a-fluorination of aldehydes. Enders and Hiittl have focused on the use of Selectfluor for the a-fluorination of aldehydes and ketones [24a], For the aldehydes, no enantiomeric excess was reported using L-proline as the catalyst. In an attempt to perform direct enantioselective a-fluorination of ketones, cyclohexanone was used as the model substrate and a number of chiral amines were tested for their enantioselective properties however, the enantiomeric excess was rather low and in the range of 0 to 36% ee. 

The rates, the products, and the stereochemistry of the hydrogenation of ketones over platinum metals may depend greatly on catalyst, solvent, and acidic or alkaline additive, impurities, as well as the structure of ketones. Breitner et al.97 studied the rates of hydrogenation of isobutyl methyl ketone, cyclohexanone, and cyclopentanone over 5% Pd-C, Pt-C, Rh-C, and Ru-C catalysts in various solvents (AcOH, H20, 0.5M aqueous NaOH, 0.5M aqueous HC1, MeOH, and EtOAc). Palladium was always not active irrespective of the solvents used. Over Pt-C all three ketones were hydrogenated most rapidly in H20 and 0.5M aqueous HC1, while in 0.5M aqueous NaOH only cyclohexanone was hydrogenated in a satisfactory rate. With Rh-C and Ru-C all the ketones were hydrogenated best in H20 and 0.5M aqueous NaOH, and the presence of HC1 depressed the rates of hydrogenation, especially for Ru-C. 

ACGIH TLV TWA 20 ppm, STEL 50 ppm (skin) Confirmed Animal Carcinogen DFG MAK Confirmed Animal Carcinogen with Unknown Relevance to Humans NIOSH REL (Ketone (Cyclohexanone)) TWA 100 mg/m3 DOT CLASSIFICATION 3 Label Flammable Liquid... 

Dojlido, J., Stodja, A., Gantz, E., Kowaslski, J. (1984) Biodegradation of methyl ethyl ketone, cyclohexanone, and cyclohexanol in sewage and surface water. Arch. Ochr. Srodowiska. 1, 115-123. 

Potassium triisopropoxyborohydride, a mild selective reducing agent, rapidly converted ketones and aldehydes to the corresponding alcohols, while many common functional groups were inert.The reaction of potassium hydride with triphenylborane produced the triphenylborohydride, which is highly hindered and which exhibited excellent chemoselectivity between ketones. Cyclohexanone was reduced in preference to cyclopentanone (97 3) and 4-heptanone (99.4 0.6), while methyl ketones were more reactive than 4-heptanone (2-heptanone, 94 6 acetophenone, 97.8 2.2). 

The common standards are re-butane, isooctane, benzene, p-xylene, naphthalene, methyl ethyl ketone, cyclohexanone, and cyclo-hexanol. 

As described above, zeolites can also act as solid base catalysts when the Si Al ratio is low and the extra framework cation is a large one such as The most basic common exchanged zeolite is CsX. With this material the aldol condensation of cyclooctanone with benzaldehyde gave only the monobenzylidene compound (Eqn. 10.23) 5 while reactions using piperidine, m nesium oxide or amorphous cesium aluminosilicate gave both the mono- and di-benzylidene products(Eqn. 10.12). The smaller ketones, cyclohexanone and... 

This reaction was done with a variety of substituted aromatic and aUphalic carboxylic acids and aldehydes. Unlike the aromatic aldehydes that produced the corresponding products in high purity and good yields, reactions with aliphatic aldehydes produced several unidentified substances together with the desired a-(acyloxy)carboxamide products. In the case of ketones, cyclohexanone was successfully included into this 3-CC process and gave the corresponding products in reasonable yield, but attempts to use acetophenone as the carbonyl substrate failed. The inactivity of the acetophenone in this reaction may be due to the steric effect of the relatively bulky phenyl group. 

The vinyl-lithium may be combined directly with the carbon electrophile such as an alkyl halide or a carbonyl compound, or converted into another vinyl derivative such as the silane for later development. Many common examples use cyclic ketones. Cyclohexanone gives the Z-vinyl-lithium6 38 (Li has a lower priority than C) and hence the ii-vinyl silane 39 (Si has a higher priority than C) in good yield on trapping with Me3SiCl. 

Linear polyurethanes dissolve in various solvents such as ketones (methyl ethyl ketone, cyclohexanone, etc.), acetate alkyl esters (methyl acetate, butyl acetate), THF, dimethylformamide, methylene chloride, trichloroethane, etc. 

Aromatization. Enamines of 6-membered cyclic ketones (cyclohexanone, a-tetra-lone, p-tetralone,...) yield arylamines on treatment with SnCU in CH2CI2 at room temperature. [SbCU is less efficient]... 

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