Showing papers on "Cyclohexanone published in 1986"
TL;DR: In this paper, the cyclohexanone-oxime rearrangement catalyzed by a series of HNaY zeolites was studied in a fixed-bed reactor with continuous plug flow at atmospheric pressure and 335°C.
119 citations
Patent•
09 Jul 1986
TL;DR: In this paper, a catalytic process for preparing cyclohexanone-oxime was proposed, where the catalyst was a highly crystalline substance containing SiO₂ and having a zeolitic structure.
Abstract: A catalytic process for preparing cyclohexanone-oxime by reacting cyclohexanone with NH₃ and H₂O₂ in the liquid phase, wherein the catalyst substantially consists of a highly crystalline substance containing SiO₂ and having a zeolitic structure.
72 citations
TL;DR: In this article, the mechanism of the alkylation of metalated Schiff s bases (azaallyilithiums) has been investigated in the context of the synthesis of cyclohexanone phenylimine.
Abstract: Treatment of 2-carbomethoxycyclohexanone dimethylhydrazone with lithium diisopropylamide as a hydrocarbon solution afforded the corresponding lithiated hydrazone as a tetrahydrofuran solvate 1. An X-ray crystallographic structure determination showed 1 to be dimeric in the solid state. Solution molecular weight and spectroscopic studies in aromatic hydrocarbon solvents uncovered a dissociative process involving either monomer-dimer equilibrium or solvent dissociation. Treatment of cyclohexanone phenylimine with lithium diisopropylamide in hydrocarbon solution afforded the corresponding lithiated derivative as the diisopropylamine solvate 2. An X-ray crystallographic structure determination showed 2 to exist as a dimer with significant disorder in the cyclohexenyl and phenyl moieties. Lithium-xrbon contacts of the q3-azaallyl type were not observed. 6Li and \"C NMR studies showed 2 to exist as a 2:l mixture of two rapidly equilibrating forms. By titration of the corresponding solvent-free anion (2sobcnt.frce) with diisopropylamine, the two species were shown to be bis-solvated dimers in close analogy to the solid-state structure. The structures are discussed in light of the stereochemistry of imine alkylation and the syn effect of lithiated imines. We became interested in the mechanism of the alkylations of metalated Schiff s bases (azaallyilithiums).l~* Although on first inspection the C=N-R moiety and C=O ketone carbonyl group appear to be interchangeable, studies by Corey, Enders, Fraser, and others uncovered some notable differences in the alkylation stere~selectivities.~~~ For example, metalated Schiffs bases derived from conformationally anchored cyclohexanones exhibit axial (1) Collum, D. B.; Kahne, D.; Gut, S. A,; Dehe, R. T.; Mohamadi, F.; Wanat, R. A,; Clardy, J.; Van Duyne, G. J . Am. Chem. Soc. 1985,106,4865. (2) Wanat, R. A,; Collum, D. B. J . Am. Chem. Soc. 1985, 107, 2078. (3) Reviews of the chemistry of metalated Schiffs bases: (a) Hickmott, P. W. Tetrahedron 1982, 38, 1975. (b) Enders, D. In Currenf Trends in Organic Synthesis; Nozaki, H., Ed.; Pergamon: New York, 1983. (c) Whitesell, J. K.; Whitesell, M. A. Synthesis 1983, 517. (d) Fraser, R. R. In Comprehensive Carbanion Chemistry; Elsevior: New York, 1980. (4) The nitroso derivatives of 4-terr-butylpiperidines exhibit high alkylation stereoselectivities that seem to imply a close mechanistic relationship to lithiated Schiffs base alkylations (cf. ref 3d). alkylation selectivities of a significantly greater magnitude than those of the corresponding ketone enolates (eq l).5 In the specific case of dimethylhydrazone alkylation, the axial selectivities are sensitive to substituents on the carbanionic carbon. Cyanoand (methy1thio)-substituted lithiated hydrazones alkylate with high axial selectivities. However, the corresponding carbomethoxysubstituted derivative exhibits a lower selectivity more characteristic of ketone enolates. Equally intriguing is the propensity of the 3and 6-substituted lithiated cyclohexanone dimethylhydrazones to alkylate from the more hindered face.' ( 5 ) Huff, B. J. L.; Tuller, F. N.; Caine, D. J. Org. Chem. 1969, 34, 3070. House, H. 0.; Umen, M. J. J. Org. Chem. 1973, 38, 1000. Howe, R.; McQuillin, F. J. J. Chem. SOC. 1958, 1194. Kuwajima, 1.; Nakamura, E. J . Am. Chem. SOC. 1975, 97, 3257. Djerassi, C.; Osiecki, J.; Eisenbraun, E. J. J. Am. Chem. Soc. 1%1,83,4433. House, H. 0.; Tefertiller, B. A,; Olmstead, H. D. J. Org. Chem. 1968,33,935. Kuehne, M. E. J . Org. Chem. 1970,35, 171. Kuwajima, I.; Nakamura, E.; Shimizu, M. J . Am. Chem. Soc. 1982,204, 1025. 0002-7863/86/1508-3415$01.50/0
71 citations
TL;DR: In this paper, a novel synthesis of cyclopropanols from α-haloketones or 1,2-dibenzoylethane is described, which can be used for the iodomethylation of carbonyl compounds giving iodohydrins.
63 citations
TL;DR: In this article, the reduction of cyclopenta-and cyclohexanone 2-carboxyesters by various yeast and mould strains was shown to produce different amounts of isomeric beta-hydroxyesters with predominant (1 S ) stereochemistry.
63 citations
TL;DR: In this paper, a general method for the preparation of 1,5-dicarbonyl compounds and six membered ring annelation is described, which involves the reaction of hemiacetal vinylogs with enol ethers 2 or 3 in the presence of a Lewis acid.
51 citations
TL;DR: In this paper, a catalytic reduction of ketones with CO and water under mild conditions has been developed, and a catalyst cycle has been proposed, with a turnover frequency of 1.2 min−1, which is increased by a factor of ca. 6 by the presence of sodium carbonate.
44 citations
TL;DR: In this paper, 3-, 4-Pyridyl and 4-quinolyl Grignard reagents were generated by the reaction of the corresponding phenyl sulfoxides with PhMgBr and give the adducts upon treatment with various aldehydes and ketones.
38 citations
TL;DR: In this paper, a new synthesis of unsymmetrical azines utilizing diethyl phosphorohydrazidate as starting material and based on Wadsworth-Emmons type phosphoramidate approach is described.
Abstract: A new synthesis of unsymmetrical azines utilizing diethyl phosphorohydrazidate as starting material and based on Wadsworth-Emmons type phosphoramidate approach is described.
28 citations
TL;DR: Laminated zinc/silver-graphite reacts rapidly at low temperatures with α-bromo- and α-chloro-alkanoates and cyclic ketones allowing high yielding and even stereospecific Reformatsky reactions.
Abstract: Laminated zinc/silver–graphite reacts rapidly at low temperatures with α-bromo- and α-chloro-alkanoates and cyclic ketones allowing high yielding and even stereospecific Reformatsky reactions.
28 citations
TL;DR: In this article, enol phosphates, readily prepared from ketone enolates and dialkyl phosphorochloride, can be converted to β-ketophosphonates by treatment with strong base.
TL;DR: The selective oxidation of saturated hydrocarbons can be carried out using triplet oxygen, pyridine, trifluoroacetic acid, and an iron catalyst in an unicellular electrochemical cell (Gif-Orsay system) as mentioned in this paper.
Abstract: The selective oxidation of saturated hydrocarbons can be carried out using triplet oxygen, pyridine, trifluoroacetic acid, and an iron catalyst in an unicellular electrochemical cell (Gif–Orsay system), cyclododecane, adamantane, and cyclo-octane being oxidised in 17–30 mmolar amounts with improved coulombic yields of up to ∼30% being attainable; oxidation of cyclohexane in 48 mmolar amounts gave cyclohexanone with some cyclohexanol in ∼40% coulombic yield, and similar yields were obtained on a 140–167 mmolar scale (saturated solution of hydrocarbon) with addition of electron transfer reagents and enough water to give two layers (good stirring) and satisfactory conductivity.
TL;DR: In this paper, the catalytic activity of IrH(COD)L 2 complexes in hydrogen transfer reactions from alcohols to cyclohexanone is described, and the related AsPh 3 ) 2 complexes have been prepared from iridium chloro-diene compounds.
TL;DR: In this paper, it was shown that cyclohexen-hexen -2 one and g-nitrostyrene can be reduced with BNAH, which was previously reported to be inert or very unreactive toward this reagent.
TL;DR: In this paper, the authors propose an approach for the formation (par desilylation des composes du titre) d'azolemethanures-1 via the formation of carbanions methyl-1 azolures-5.
Abstract: Obtention principalement d'azoleethanols-1 via la formation (par desilylation des composes du titre) d'azolemethanures-1; obtention egalement de methyl-1 azolemethanols-5 via les carbanions methyl-1 azolures-5
TL;DR: In this paper, the pyrrole derivatives were converted via O(2-hydroxyethy)-oximes into pyrone derivatives in satisfactory overally yields, including cyclohexanone, cycloheptanone and cyclo-octanone.
Abstract: Acetophenone, cyclohexanone, cycloheptanone, cyclo-octanone, and heptan-4-one were converted, via their O-(2-hydroxyethy)-oximes [(5), (6a), (6b), (6c), and (8)] into the pyrrole derivatives [(2b), (7a), (7b), (7c), and (9), respectively] in satisfactory overally yields.
TL;DR: In this paper, the preparation of 3-stannyl-1-silyloxycyclohex-1enes and their use as synthons for α,β-dianions for cyclohexanone are described.
TL;DR: Synthese de la dibutyl-5,11 dodecahydro-1,2,3,4,6,7,9,10,12,13,14,15 acridino [4,3-b] benzo [j] phenanthroline -1,10
Abstract: Synthese de la dibutyl-5,11 dodecahydro-1,2,3,4,6,7,9,10,12,13,14,15 acridino [4,3-b] benzo [j] phenanthroline-1,10
TL;DR: The most suitable kinetic equation for the selective hydrogenation of phenol to cyclohexanone on a 0.96wt.% Pd-9.63w.% CaO-alumina (Harshaw AL-3965) catalyst is determined among a series of models based on Langmuir-Hinshelwood-Hougen-Watson theory as discussed by the authors.
Abstract: The most suitable kinetic equation for the selective hydrogenation of phenol to cyclohexanone on a 0.96wt.% Pd-9.63wt.%CaO-alumina (Harshaw AL-3965) catalyst is determined among a series of models based on Langmuir-Hinshelwood-Hougen-Watson theory.
TL;DR: In this article, a new nickel boride catalyst, DBNi, was proposed for hydrogenation of cyclohexanone and nitrobenzene using diborane as reducing agent.
TL;DR: In this paper, the effect of the concentration of acid, monomer, and V5+ on graft yield have been studied and a mechanism and derivation of rate expression for the grafting process were presented.
Abstract: Graft copolymerization of methyl methacrylate (MMA) was carried out on jute fibers using a V5+ -cyclohexanone redox initiator system. The effect of the concentration of acid, monomer, and V5+ on graft yield have been studied. In order to obtain optimum conditions of grafting, the effects of temperature, acid, reaction medium, solvent, and some inorganic salts on graft yield have been investigated. The most remarkable features of the investigation include the proposition of a mechanism and derivation of rate expression for the grafting process. More than 100% grafting could be achieved with the present system.
TL;DR: In this article, the chiral imines prepared from cyclohexanone and methoxy amines (2b, 4c, 6d, and 7d) derived from D-camphor derivatives provided, after hydrolysis, optically active 2-alkylcyclohexansones (9) in high enantiomeric purities of up to 99.5%.
Abstract: Metalation and alkylation of the chiral imines prepared from cyclohexanone and methoxy amines (2b, 4c, 6d, and 7d) derived from D-camphor derivatives provided, after hydrolysis, optically active 2-alkylcyclohexanones (9) in high enantiomeric purities of up to 99.5%.
TL;DR: In situ generated chloromethyl-lithium reacts at −78 °C with different aldehydes and ketones to afford, after lithiation with lithium powder, terminal and exocyclic olefins as discussed by the authors.
Abstract: The in situ generated chloromethyl-lithium reacts at –78 °C with different aldehydes and ketones to afford, after lithiation with lithium powder, terminal and exocyclic olefins.
Patent•
14 Oct 1986TL;DR: In this paper, shape-selective oxidation of cyclic ketones to lactone and/or omega-hydroxycarboxylic acid products in the presence of a zeolite catalyst composition is described.
Abstract: This invention provides process embodiments for shape-selective oxidation of cyclic ketones to lactone and/or omega-hydroxycarboxylic acid products in the presence of a zeolite catalyst composition such as ZSM-5 or zeolite Beta. Cyclohexanone can be converted to epsilon-caprolactone or 6-hydroxycaproic acid as a main product under selected conditions.
TL;DR: In the presence of coordinating ligands, rhodium(II) acetate dimer Rh2(OCOCH3)4 shows a good catalytic activity towards the hydrogen transfer from 2-propanol to cyclohexanone and some other unsaturated compounds as mentioned in this paper.
Abstract: In the presence of some coordinating ligands, rhodium(II) acetate dimer Rh2(OCOCH3)4, shows a good catalytic activity towards the hydrogen transfer from 2-propanol to cyclohexanone and some other unsaturated compounds. The catalytic activity is the function of the nature of ligands and their ratio to Rh2(OCOCH3)4. The most active system is obtained using Rh2(OCOCH3)4 and 2,2′-bipyridine in molar ratio 1:6.
TL;DR: In this paper, the effect of impregnating metal on carbon catalysts with liquid films, immiscible with the bulk solvent, on rate and selectivity in liquid-phase hydrogenations has been investigated.
Abstract: The effect of impregnating metal on carbon catalysts with liquid films, immiscible with the bulk solvent, on rate and selectivity in liquid-phase hydrogenations has been investigated. Both acid and alkaline films have been used with benzene and phenol as the reactant. The bifunctional character of such catalysts has been demonstrated and a substantial improvement in selectivity for the hydrogenation of phenol to cyclohexanone has been achieved. The factors contributing to the observed phenomena in such multiphase catalytic reactions are discussed.