1117-89-1Relevant articles and documents
Scharpen et al.
, p. 2010,2011 (1972)
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Herschbach,Kirsher
, p. 728 (1958)
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Ryan,Speier
, p. 895,896, 897 (1964)
Mechanism of Deuterium Addition and Exchange of Propene over Silica-supported Gold and Silver Catalysts
Naito, Shuichi,Tanimoto, Mitsutoshi
, p. 4115 - 4124 (1988)
The mechanism of the C3H6-D2 reaction over silica-supported Au and Ag catalysts has been studied by applying microwave spectroscopy as well as kinetic measurements.A large kinetic isotope effect was observed for the rate of propane formation between the C3H6-H2 andC3H6D2 reactions, indicating that the hydrogen dissociation is the rate-determining step.Both deuterium addition and exchange processes proceeded via an associative mechanism involving n-propyl as well as s-propyl species, although the methyl hydrogen of propene was less active for exchange through this process.In addition, intramolecular 1,3- and 2,3-hydrogen-shift processes were observed for the first time; they proceeded only in the presence of gaseous hydrogen and caused the exchange of the methyl hydrogen of propene.The characteristic features of supported Group IB metals in this reaction are compared with those of Group VIII metals, and the possible structures of reaction intermediates are discussed in detail.
Remarkable Dispersion Effect of TiO2 Catalyst on Silica Support in Propene - Deuterium Addition and Exchange Reaction
Naito, Shuichi,Tanimoto, Mitsutoshi
, p. 2145 - 2148 (1990)
Investigation on the effect of dispersing small particles of TiO2 over silica upon the rate and mechanism of propene-deuterium reaction revealed that lower loading catalysts (1-8 wtpercent) exhibit markedly different catalytic behavior from that over unloaded TiO2.
Novel Support Effects on the Mechanism of Propene-Deuterium Addition and Exchange Reactions over Dispersed ZrO2
Naito, Shuichi,Tanimoto, Mitsutoshi
, p. 306 - 313 (1995)
The effect on the rate and mechanisms of propene-deuterium reactions of dispersing ZrO2 on various supports such as silica, alumina, and titanium dioxide has been studied by microwave spectroscopic analysis of monodeuteropropene as well as by kinetic investigation.By dispersal of ZrO2 on these supports, the rate of the C3H6-D2 reactions is increased considerably compared to that over unsupported ZrO2, with the decrease of activation energy.Hydrogen exchange in propene proceeds simultaneously with addition via the associative mechanism through n-propyl and s-propyl intermediates.Through XPS analysis of ZrO2/SiO2, it was found that a monolayer of ZrO2 is formed over the silica support.The monolayer catalyst exhibits catalytic behavior quite different from that of unsupported ZrO2.On the other hand, alumina surfaces modified by ZrO2 layers may be the main active sites in the case of ZrO2/Al2O3.The marked enhancement of the reaction rate in the lower loading region of ZrO2/TiO2 may be explained by the strong interaction of atomically dispersed zirconium ions with active centers on TiO2
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Barton,T.J.,Tillman,N.
, p. 6711 (1987)
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Carbon Acidity. 58. Hydrogen Isotope Exchange Kinetics of Propylene with Lithium Cyclohexylamide
Boerth, Donald W.,Streitwieser, Andrew Jr.
, p. 6443 - 6447 (1981)
Rates for hydrogen isotope exchange with lithium cyclohexylamide (LiCHA) in cyclohexylamine-N,N-d2 (CHA-D2) and cyclohexylamine (CHA) are compared for propene and toluene.Benzyl hydrogens in toluene were found to be 6.2 times more reactive than allyl hydrogens in propene.Experimental primary isotope effects are also reported for propene: kD(exptl)/kT(exptl)=2.9, kH(exptl)/kT(exptl)=30, and kH(exptl)/kD(exptl)=10.2.Derived internal return values show comparable values for propene and toluene.Analysis of polydeuteration rates shows that exchange is accompanied by complete equilibration of allyl positions.The high isotope effects and comparable acidities and internal return imply a transition state for propene which resembles that of toluene.An equilibrium pKa on the CsCHA scale of ca. 43 is deduced for propene.
Hironaka,Hirota
, p. 2437 (1966)
Cobalt-Catalyzed Deprotection of Allyl Carboxylic Esters Induced by Hydrogen Atom Transfer
Li, Nan,Gui, Yizhen,Chu, Mengqi,You, Mengdi,Qiu, Xiaohan,Liu, Hejia,Wang, Shiang,Deng, Meng,Ji, Baoming
supporting information, p. 8460 - 8464 (2021/11/13)
A brief, efficient method has been developed for the removal of the allyl protecting group from allyl carboxylic esters using a Co(II)/TBHP/(Me2SiH)2O catalytic system. This facile strategy displays excellent chemoselectivity, functional group tolerance, and high yields. This transformation probably occurs through the hydrogen atom transfer process, and a Co(III)-six-membered cyclic intermediate is recommended.
Decomposition of 1,1-dimethyl-1-silacyclobutane on a tungsten filament - Evidence of both ring C-C and ring Si-C bond cleavages
Tong,Shi
experimental part, p. 215 - 222 (2010/10/04)
The decomposition of 1,1-dimethyl-1-silacyclobutane (DMSCB) on a heated tungsten filament has been studied using vacuum ultraviolet laser single photon ionization time-of-flight mass spectrometry. It is found that the decomposition of DMSCB on the W filament to form ethene and 1,1-dimethylsilene is a catalytic process. In addition, two other decomposition channels exist to produce methyl radicals via the Si-CH3 bond cleavage and to form propene (or cyclopropane)/dimethylsilylene. It has been demonstrated that both the formation of ethene and that of propene are stepwise processes initiated by the cleavage of a ring C-C bond and a ring Si-C bond, respectively, to form diradical intermediates, followed by the breaking of the remaining central bonds in the diradicals. The formation of ethene via an initial cleavage of a ring C-C bond is dominant over that of propene via an initial cleavage of a ring Si-C bond. When the collision-free condition is voided, secondary reactions in the gas-phase produce various methyl-substituted 1,3-disilacyclobutane molecules. The dominant of all is found to be 1,1,3,3-tetramethyl-1,3-disilacyclobutane originated from the dimerization of 1,1-dimethylsilene. Copyright
