33083-83-9Relevant academic research and scientific papers
Catalytic ketonisation over oxide catalysts. Part IX. Single step synthesis of aliphatic saturated and unsaturated C11 - C 13 ketones from carboxylic acids
Glinski,Gibka
, p. 299 - 302 (2007/10/03)
Metameric undecan-x-ones (x = 2-6), dodecan-y-ones (y = 2-5), tridecan-z-ones (z = 4-7) and two unsaturated aliphatic ketones were prepared by vapor phase ketonisation of the appropriate monocarboxylic acids in the presence of 20 wt% MnO2/Al2O3 catalyst under flow conditions. The ketones were obtained in yields between 48 and 89% in a multigram scale (80-250 g). Their physical and spectral data have been determined.
Semivolatile and volatile compounds in combustion of polyethylene
Font, Rafael,Aracil, Ignacio,Fullana, Andrés,Conesa, Juan A.
, p. 615 - 627 (2007/10/03)
The evolution of semivolatile and volatile compounds in the combustion of polyethylene (PE) was studied at different operating conditions in a horizontal quartz reactor. Four combustion runs at 500 and 850°C with two different sample mass/air flow ratios and two pyrolytic runs at the same temperatures were carried out. Thermal behavior of different compounds was analyzed and the data obtained were compared with those of literature. It was observed that α,ω-olefins, α-olefins and n-paraffins were formed from the pyrolytic decomposition at low temperatures. On the other hand, oxygenated compounds such as aldehydes were also formed in the presence of oxygen. High yields were obtained of carbon oxides and light hydrocarbons, too. At high temperatures, the formation of polycyclic aromatic hydrocarbons (PAHs) took place. These compounds are harmful and their presence in the combustion processes is related with the evolution of pyrolytic puffs inside the combustion chamber with a poor mixture of semivolatile compounds evolved with oxygen. Altogether, the yields of more than 200 compounds were determined. The collection of the semivolatile compounds was carried out with XAD-2 adsorbent and were analyzed by GC-MS, whereas volatile compounds and gases were collected in a Tedlar bag and analyzed by GC with thermal conductivity and flame ionization detectors.
New version of the TEMPO-based catalytic system for the oxidation of alcohols to aldehydes
Kowalczyk,Skarzewski
, p. 1413 - 1417 (2007/10/03)
A new chemoselective catalytic system for the title oxidation was developed using methyltrioxorhenium (3 mol%), KBr (10 mol%) and TEMPO (3 mol%) as co-catalysts and Oxone as a terminal oxidant.
Preparation of aldehydes or ketones from alcohols
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, (2008/06/13)
A process for preparing an aldehyde or ketone comprising reacting a primary or secondary alcohol with oxygen in the presence of a base, a catalytic amount of a copper salt and a suitable lignad under anhydrous conditions.
One-pot dialkylation of allylphenylsulfide induced by aminoalkoxides- activated NaNH2. Application to the synthesis of unsymmetrical ketones
Choppin, Sabine,Gros, Philippe,Fort, Yves
, p. 9261 - 9268 (2007/10/03)
It is shown that the activation of NaNH2 by sodium aminoalkoxides, leading to new superbases, induced an efficient one-pot dialkylation of allylphenylsulfide. The regioselectivity of the reaction (α,α' vs α,γ) was found as strongly dependent on the nature of the alkyl halide. As an application, α,γ dialkylated products were efficiently converted Into the corresponding unsymmetrical ketones.
Chemoselective conversion of conjugated nitroalkenes into ketones by sodium borohydride-hydrogen peroxide: A new synthesis of 4-oxoalkanoic acids, dihydrojasmone and (±)exo-brevicomin
Ballini,Bosica
, p. 723 - 726 (2007/10/02)
A new, simple, cheap, and practical procedure for the direct transformation of α,β-unsaturated nitroalkenes into ketones has been realized by the NaBH4/H2O2 system. By this method, other functional groups such as C-C double bonds, ketals or aromatic nitro groups were preserved. Application of this methodology to the preparation of 4-oxoalkanoic acids, dihydrojasmone, and (±)-exobrevicomin is also reported.
Electrochemical Wacker Type Reaction with a Double Mediatory System Consisting of Palladium Complex and Tri(4-bromophenyl)amine
Inokuchi, Tsutomu,Ping, Liu,Hamaue, Fumihiro,Izawa, Miyoko,Torii, Sigeru
, p. 121 - 124 (2007/10/02)
The electrochemical Wacker type oxidation of terminal olefins by using palladium chloride or palladium acetate and tri(4-bromophenyl)amine as a recyclable mediator in either a divided cell or an undivided cell afforded the corresponding methyl ketones in good yields.
About the Reaction between n-Alkanes and Aluminium Nitrate-nonahydrate
Minkov, Dimiter,Lavcieva, Dimitrina,Kumanova, Bogdana
, p. 849 - 855 (2007/10/02)
The reaction between n-alkanes (C10 - C13) and aluminium nitrate-nonahydrate in the temperature range 353-403 K, time of contact 12 h and mole ratio nitrating agent: hydrocarbon from 1:2 was investigated.The product obtained was separated on silicagel.The fractions separated by adsorption chromatography were studied by i.r.- and combined GC/MS spectroscopy.Only alkyl nitrates were obtained.The oxidation processes yield aldehydes, ketones and nitrate carboxylic acids.The model reaction with n-undecane shows that undecyl-3-nitrate (5), undecanal (6), undecan-5-on (7) and nitrate undecanic acid (8) are obtained.
STEREOCHEMICAL ASSIGMENT BY MASS SPECTROMETRY. DOUBLE BOND GEOMETRICAL ISOMERS OF 3,5-DIALKYLCYCLOHEXYLIDENE ACETIC ACID ESTERS AND 3-ALKYL-2-ALKENOATES
Merksammer, Israel,Mandelbaum, Asher
, p. 775 - 780 (2007/10/02)
Mass spectrometry is best physical method for the configurational assignment of E- and Z-3,5-dialkylcyclohexylidene acetic acid esters 1 and E- and Z-3-alkyl-2-alkenoates 2.The homoallylic cleavage resulting in the loss of the C-3 and C-5 alkyl groups from 1 and of the two δ-alkyls from 2 is a stereospecific process: the loss of the group which is adjacent to the carbonyl is significantly preferred.The stereospecifity of this fragmentation is interpreted in terms of a hidden hydrogen transfer preceding the carbon-carbon bond cleavage.
Low Temperature Free-Radical Reactions Initiated with tert-Butyl p-Benzoylperbenzoate. Selective Acyl Radical Additions to Substituted Olefins
Gottschalk, Peter,Neckers, D. C.
, p. 3498 - 3502 (2007/10/02)
Competition experiments involving acyl radical additions to simple and electron-deficient olefins showed a definite preference for acylation of the latter olefin.This selectivity was significantly enhanced by using low temperature initiation with tert-butyl p-benzoylperbenzoate (1), which allows selective initiation of free-radical cyclization reactions that have synthetic importance.
