F+:Highly flammable;
109-67-1Relevant articles and documents
Photooxidation of n-heptanal in air: Norrish type I and II processes and quantum yield total pressure dependency
Tadic, Jovan M.,Juranic, Ivan O.,Moortgat, Geert K.
, p. 135 - 140 (2002)
Dilute mixtures of n-heptanal in synthetic air (up to 100 ppm) were photolyzed with fluorescent UV lamps (275-380 nm) at 298 K. The main photooxidation products, identified and quantitatively analyzed by FTIR spectroscopy, were pent-1-ene, CO, vinyl alcoh
High yields of piperylene in the transfer dehydrogenation of pentane catalyzed by pincer-ligated iridium complexes
Kumar, Akshai,Hackenberg, Jason D.,Zhuo, Gao,Steffens, Andrew M.,Mironov, Oleg,Saxton, Robert J.,Goldman, Alan S.
, p. 368 - 375 (2017)
Conjugated dienes are desirable reagents for several important applications. We report that sterically uncrowded PCP-pincer iridium complexes, including precursors of (iPr4PCP)Ir and (Me2tBu2PCP)Ir, catalyze the transfer d
Synthesis and catalytic investigation of organophilic Pd/graphite oxide nanocomposites
Mastalir,Szabó,Király,Dékány
, p. 104 - 107 (2012)
Low-loaded, organophilic Pd/graphite oxide (Pd/GO) nanocomposites were synthesized from different Pd complex precursors by applying graphite oxide as a host material and tetradecyltrimethylammonium bromide (C14TAB) as a stabilizer. Structural investigation of the Pd/GO samples was performed by ICP-AES, XRD, N2 sorption and TEM measurements. It was found that monodispersed Pd nanoparticles were formed, ranging in size between 1 and 6 nm, both on the external surface and in the interlamellar space of GO. The samples proved to be highly active and selective catalysts for liquid-phase alkyne hydrogenations. The variation in the catalytic performances was attributed to the difference in the amount of interlamellar Pd particles, which participated in the reactions as active sites.
Hg(63P1) Photosensitization of Cyclohexanone. Role of Triplet Biradical Intermediates
Baulch, D. L.,Lenney, Colburn P. W.,Montague, D. C.
, p. 1803 - 1812 (1981)
Hg(63P1) photosensitization of cyclohexanone results in the formation of pent-l-ene, cyclopentane and hex-5-enal, just as observed in the direct photolysis.As the pressure of added SF6 or Ar bath gas is increased, both the total product quantum yield and that of the hydrocarbon products decrease, while that of hex-5-enal increases.A comprehensive mechanism, differing in detail from those previously proposed, is now formulated to account quantitatively for the experimental observations.Two sequentially formed, energy randomized, vibrationally excited triplet biradicals are believed to be the important intermediates that lead to product formation.Thus α-C-C bond cleavage of triplet cyclohexanone yields an acyl-alkyl biradical. 3B*, that can give rise to both hex-5-enal and also, by loss of CO, to the penta-l.5-diyl biradical, 3PD*, the precursor of the hydrocarbon products.Rate constants for intersystem crossing of the two biradicals are deduced along with that for the fragmentation of 3B*.An RRKM treatment of this decomposition suggests that the observed rate constant is best fitted using a biradical excitation energy calculated by assuming a heat of formation for 3B greater than the value computed by conventional methods, which neglect electronic interaction.In addition, relative rate constants are obtained for the intramolecular disproportionation and cyclisation of 1B and 1PD when both vibrationally excited and thermalized.It is concluded that the critical energy for ring closure of 1PD is greater than that for isomerization to pent-l-ene.
A Mechanistic Study of the Rhodium-Catalyzed Cyclization of 4-Hexenals. Reactions of Deuterio-4-hexenals
Campbell, Richard E.,Lochow, Charles F.,Vora, Krishnakant P.,Miller, Roy G.
, p. 5824 - 5830 (1980)
In independent experiments, four carbons in the 4-pentenal skeleton have been labeled with deuterium or methyl and the fate of each label has been determined as the pentenal was transformed into a cyclopentanone derivative by RhCl(PPh3)3 (1) at 24-26 deg C.The catalyst converted 4-hexenal to 2-methylcyclopentanone (2) in CHCl3 and C6H6.Approximately equivalent amounts of hydrocarbon decarbonylation products and RhCl(CO)(PPh3)2 were also formed. 3-Methyl-4-pentenal was isomerized to 3-methylcyclopentanone by 1. 4-Hexenal possessing deuterium at C-2 was isomerized to 2 which contained deuterium at C-5. trans-4-Hexenal-1-d was cyclized to 2-3-d and 2-2-d in 9:1 ratio when the reaction was carried to a low conversion.The deuterium in the 2-3-d product was found to be cis to the C-2 CH3 group. cis-4-Hexenal-1-d was isomerized by 1 to afford 2-3-d possessing deuterium trans to the C-2 CH3 group.NMR analyses of these products were assisted by the synthesis and characterization of 2-cis-2,3-d2 by treatment of 2-methylcyclopent-2-en-1-one with D2 and 1.The 2-cis-2,3-d2 could be converted to a 1:1 mixture of 2-3-d diastereomers on treatment with HCl in MeOH/H2O.The result demonstrated that the cyclization of 4-hexenal-1-d occurred by a syn addition of the C-D bond to the olefinic bond to generate 2-3-d.The presence of C2H4 in reactin mixtures of 1 and 4-hexenal-1-d resulted in the formation of substantial 2-d0 and C2H3D.The deuterium locations in the 1-pentene, 2-pentene, and ethylcyclopropane decarbonylation products derived from reaction of 4-hexenal-1-d with 1 were determined.The results were interpreted in terms of a hydroacylation mechanism involving an acylrhodium(III) hydride complex and organometallic intermediates derived therefrom.The hydroacylation and decarbonylation products appear to be generated via common intermediates.
Faujasite silicalites for oxidative dehydrogenation of n-octane: Influence of alkali metals, gallium, and boron on catalyst activity
Ndlela, Siyabonga S.,Friedrich, Holger B.,Cele, Mduduzi N.
, (2021)
The sol-gel method was used to synthesize faujasite type silicalites bearing gallium and boron in the framework. Barium and sodium were used as charge balancing cations since isomorphic substitution of Si4+ by Ga3+ or B3+ results in a negative excess charge of the framework. The successful synthesis of this type of silicalites (GaBaY-S, BBaY-S, GaBBaY-S(IE), GaNaY-S) was confirmed using powder-XRD. SEM analysis showed that the morphology of the catalysts with respect to particle size depended on the framework metals and the charge balancing cation used. Framework Ga containing catalysts showed smaller particle size compared to B containing catalysts. Sodium also yielded a smaller particle-sized catalyst compared to barium. The catalysts were tested in the continuous flow oxidative dehydrogenation (ODH) of n-octane, and the catalytic results showed dependence on the active metal reducibility and acid-base character of the catalysts. At iso-conversion of 8 ± 1 %, the least acidic BBaY-S gave the highest selectivity to octenes (40 %) and the lowest selectivity to COx (28 %), and the most acidic GaNaY-S showed the opposite results with octenes at 17 % and COx at 56 %. The catalysts (BaBY-S and GaBBaY-S(IE) with least total acidity had the greatest quantity of strong acid sites which were attributed to Lewis acid sites, confirmed by the pyridine IR analysis. The GaNaY-S, with the highest total acidity, had the least strong acid sites.
On the product formation in 1-Butene metathesis over supported tungsten catalysts
Harmse, Liesel,Van Schalkwyk, Charl,Van Steen, Eric
, p. 123 - 131 (2010)
1-Butene metathesis was performed over 8 wt% tungsten catalysts supported on silica, silica-alumina and γ-Al2O3. Under the applied reaction conditions, 1-butene metathesis yields with a relatively large selectivity iso-butene in addition to the expected metathesis products. The isobutene selectivity is high for catalysts with a relative low activity and decreases with increasing metathesis activity. It is deduced that iso-butene formation involves surface tungsten complexes, whose formation inhibits the metathesis activity. Springer Science+Business Media, LLC 2010.
Photolysis of heptanal
Paulson, Suzanne E.,Liu, De-Ling,Orzechowska, Grazyna E.,Campos, Luis M.,Houk
, p. 6403 - 6408 (2006)
Photolysis of heptanal is investigated from an experimental and theoretical point of view. Photoexcited heptanal is believed to undergo rapid intersystem crossing to the triplet manifold and from there undergoes internal H-abstraction to form biradical intermediates. The favored γ-H abstraction pathway can cyclize or cleave to 1-pentene and hydroxyethene, which tautomerizes to acetaldehyde. Yields of 1-pentene and acetaldehyde were measured at 62 ± 7% and 63 ± 7%, respectively, relative to photolyzed heptanal. Additionally, small quantities of hexanal and hexanol were observed. On the basis of combined experimental and theoretical evidence, the remaining heptanal photolysis proceeds to form an estimated 10% HCO + hexyl radical and 30% cyclic alcohols, particularly 2-propyl cyclobutanol and 2-ethyl cyclopentanol.
The Selective Conversion of n-Pentane into Pent-1-ene via Trihydro(trans-penta-1,3-diene)bis(triarylphosphine)rhenium
Baudry, Denise,Ephritikhine, Michael,Felkin, Hugh,Zakrzewski, Janusz
, p. 1235 - 1236 (1982)
Treatment of n-pentane with heptahydridobis(triarylphosphine)rhenium and 3,3-dimethylbutene gives trihydrido(trans-penta-1,3-diene)bis(triarylphosphine)rhenium; trimethyl phosphite converts this, with high selectivity, into pent-1-ene.
Intramolecular Trapping of Alkyl- and Arylrhodium Hydride Intermediates in the Decarbonylation of Aldehydes by Chlorotris(triphenylphosphine)rhodium
Kampmeier, J. A.,Harris, S. H.,Mergelsberg, I
, p. 621 - 625 (1984)
The reaction of 5-hexenal with RhCl(PPh3)3 (1) or 2 (5) gives some cyclopentane.The reaction of 2-allylbenzaldehyde with 5 gives a good yield of indan.These cyclization reactions to give cyclopentanes, and other reactions of Δ4-enals to give cyclopropanes, reveal the presence of intermediate alkyl- and arylrhodium hydride complexes on the pathway for decarbonylation of aldehydes.The formation of nortricyclene from endo-5-norbornene-2-carboxaldehyde shows that the alkylrhodium hydride must be formed with retention of stereochemistry at the α-carbon of the aldehyde.
