3681-30-9

Upstream product

• 683-73-8 Ethylene-d4 
• 74-84-0 ethane 
• 74-85-1 ethene 
• 74-86-2 acetylene 
• 2154-63-4 1,1,2,2-tetradeuterio-ethyl 

Relevant academic research and scientific papers

Reaction of Hydrogen Peroxide with Organosilanes under Chemical Vapour Deposition Conditions

When a stream of vapour at low pressure which contained a mixture of H2O2 with an organosilane, RSiH3 (R = alkyl or alkenyl), impinged on a silicon wafer, deposition of oxide films of nominal composition RxSiO(2-0.5x), where x 3 or higher alkenyl groups. or higher alkenylgroups. Possible mechanism for the Si-C bond cleavage reaction are discussed, with energetic rearrangement of radical intermediates of type Si(H)(R)(OOH)' being favoured.

A NMR method for the analysis of mixtures of alkanes with different deuterium substitutions

13C NMR at 125.76 MHz with 1H and 2H decoupling, 2H NMR at 76.77 MHz with 1H decoupling, and 1H NMR at 500.14 MHz with 2H decoupling were employed as analytical tools to study the complex mixtures of deuterated ethanes resulting from the catalytic H-D exchange of normal ethane with gas-phase deuterium in the presence of a platinum foil. Reference samples consisting of 1:1 binary mixtures of pure normal ethane and ethane-dn (n = 1-6) were used to identify the peak positions in the 13C, 2H, and 1H NMR spectra due to each individual isotopomer, and the effect of isotopic substitution on the chemical shifts was determined in each case. While the NMR of all three nuclei worked well for the identification of the individual components of the 1:1 standard mixtures, both 1H and 2H NMR suffered from inadequate resolution when studying complex reaction mixtures because of the broadening of the lines due to 1H-1H (1H NMR) and 2H-2H (2H NMR) couplings. 13C NMR was therefore determined to be the method of choice for the quantitative analysis of the reaction mixtures. Using the 13C NMR results, a correlation that takes into account the primary and secondary isotope substitution effects on chemical shifts was deduced. This equation was used for the identification of the individual components of the mixtures, and integration of the individual observed resonances was then employed for quantification of their composition. This study shows that 13C NMR with 1H and 2H decoupling is a viable procedure for studying mixtures of deuterated ethanes. Furthermore, the additivity of the isotopic effects on chemical shifts and the transferability of the values obtained with ethane to other molecules makes this approach general for the analysis of other isotopomer mixtures.

Evidence for the activation of unstrained carbon-carbon bonds by bare transition-metal ions M+ (M = Fe, Co) without prior C-H bond activation

The metastable ion (MI) decompositions of RNH2/M+ complexes (R = (C2H5)2CHCH2, C2H5C(CH3)2CH2; M - Fe, Co) in the gas phase have been studied by tandem mass spectrometry with a four-sector instrument of BEBE configuration. The analyses of the MI spectra of isotopically labeled complexes uncover processes which inter alia demonstrate that the loss of C4H8 corresponds to a reaction in which site-specific oxidative addition of an unstrained C-C bond to the anchored transition-metal ion M+ takes place without prior C-H bond activation. The intramolecular methyl migration preceding the elimination of C4H8 is subject to a secondary kinetic isotope effect of kH/kD = 1.33 for M+ = Fe+ and kH/kD = 1.15 for M+ = Co+ per D atom. Additional processes observed correspond to the generation of molecular hydrogen, methane, ethylene and ethane. All reactions are highly specific, and mechanisms are suggested that are in keeping with the labeling data. For example, both H2 and C2H4 are formed via remote functionalization involving the ω/ (ω - 1) positions of the ethyl side chain of the amines. Ethane contains an intact ethyl group, and one hydrogen is provided via specific β-hydrogen transfer which does not involve the chemically activated CH2NH2 group. This methylene group is also inert with regard to the reductive elimination of methane from CH3CH2C(CH3)2CHNH 2/Co+. According to the labeling experiments, the intermediate from which CH4 is lberated contains an intact CH3 group that originates from the quaternary carbon center; the missing hydrogen atom is provided to roughly the same amount by both the second CH3 group of C(2) and the CH2 unit of the ethyl group. Again, the -CH2NH2 part does not serve as a hydrogen source for CH4.

Hydrogenation of Ethylene over Platinum (111) Single-Crystal Surfaces

The hydrogenation of ethylene with both hydrogen and deuterium was studied(111) platinum single-crystal surfaces under a total pressure of 110 torr and a temperature range of 300-370 K.An activation energy (Ea) of 10.8 +/- 0.1 kcal/mol and kinetic orders with respect to hydrogen and ethylene partial pressure of 1.31 +/- 0.05 and -0.60 +/- 0.05, respectively, were observed.The deuterium atom distribution in the product from the reaction with D2 peaks at 1-2 deuterium atoms per ethane molecule produced, similar to what has been reported for supported catalysts.The reaction takes place on a partially ordered carbon covered surface, where the carbonaceous deposits have a morphology similar to that of ethylidyne.However, this ethylidine does not directly participate in the hydrogenation of ethylene, since both its hydrogenation and its deuterium exchange are much slower than the ethane production.A mechanism is proposed to explain the experimental results.

Hydrogenation of Ethylene on Metal Electrodes. Part 5. Reduction of Light Ethylene on Pt in Deuteroperchloric Acid Solution and the Dual-pathway Mechanism

Electroreduction of light ethylene on a platinum electrode was conducted in a heavy-water solution of deuteroperchloric acid.Deuterium-atom distributions in the product, ethane, support the previous conclusion that ethylene diffusion is rate-controlling at potentials less positive than ca. 100 mV, whereas the surface reaction is rate-controlling at more positive potentials where the Tafel line holds.The D-atom distribution in the latter potential region reveals double maxima at - and -ethanes.This distribution is explained by the dual-pathway mechanism which assumes two reaction rates for the step C2H4(a) + H(a) C2H5(a).The difference in the reaction rate will be attributed to the difference in the adsorption state of C2H4(a) but not of H(a), since only the weakly adsorbed hydrogen atoms are active in the hydrogenation.Reduction of light ethylene with D2 on platinum in deuteroperchloric acid solution gives the same results.A computer simulation based on the above mechanism can reproduce quantitatively not only the present distributions but also others given in the literature, even those observed for the gas-phase heterogeneous reduction.