Infrared Chemiluminescence from the Reaction of Oxygen Atoms with Chloroethylenes

1974 ◽  
Vol 52 (14) ◽  
pp. 2608-2612 ◽  
Author(s):  
S. J. Arnold ◽  
G. H. Kimbell ◽  
D. R. Snelling
Keyword(s):  
Initial Step ◽  
Reaction Step ◽  
Vibrationally Excited ◽  
Cis And Trans ◽  
Oxygen Atoms

Infrared chemiluminescence from vibrationally excited CO and from vibrationally excited HCl was observed when C2H3Cl, 1,1-C2H2Cl2, cis- and trans-1,2-C2H2Cl2, or C2HCl3 was introduced into a stream of oxygen atoms. The mechanisms describing the reactions of oxygen atoms with these molecules are discussed in detail. The initial step is postulated to involve the formation of an aldehyde and a carbene. The reaction step responsible for the formation of CO† is postulated to be[Formula: see text]and for HCl†[Formula: see text]

Infrared Chemiluminescence from the Reactions of Oxygen Atoms with Halomethanes

1974 ◽  
Vol 52 (2) ◽  
pp. 271-280 ◽  
Author(s):  
S. J. Arnold ◽  
G. H. Kimbell ◽  
D. R. Snelling
Keyword(s):  
Reaction Step ◽  
Vibrationally Excited ◽  
Oxygen Atoms

Infrared chemiluminescence from vibrationally excited CO was observed when CH3Cl, CH2Cl2, CHCl3, or CH2Br2 was introduced into a stream of oxygen atoms. Emission from vibrationally excited HCl was also observed from CH2Cl2 and CHCl3. The mechanisms describing the reactions of oxygen atoms with these molecules are discussed in detail. The reaction step responsible for the formation of CO† is postulated to be[Formula: see text]and for HCl†[Formula: see text]

Active site densities, oxygen activation and adsorbed reactive oxygen in alcohol activation on npAu catalysts

2016 ◽  
Vol 188 ◽  
pp. 57-67 ◽  
Author(s):  
Lu-Cun Wang ◽  
C. M. Friend ◽  
Rebecca Fushimi ◽  
Robert J. Madix
Keyword(s):  
Selective Oxidation ◽  
Activation Barrier ◽  
Initial Step ◽  
Temporal Analysis ◽  
Adsorbed Oxygen ◽  
Transient Pressure ◽  
Pulse Reaction ◽  
Dissociation Probability ◽  
Oxidation Of Methanol ◽  
Oxygen Atoms

The activation of molecular O2 as well as the reactivity of adsorbed oxygen species is of central importance in aerobic selective oxidation chemistry on Au-based catalysts. Herein, we address the issue of O2 activation on unsupported nanoporous gold (npAu) catalysts by applying a transient pressure technique, a temporal analysis of products (TAP) reactor, to measure the saturation coverage of atomic oxygen, its collisional dissociation probability, the activation barrier for O2 dissociation, and the facility with which adsorbed O species activate methanol, the initial step in the catalytic cycle of esterification. The results from these experiments indicate that molecular O2 dissociation is associated with surface silver, that the density of reactive sites is quite low, that adsorbed oxygen atoms do not spill over from the sites of activation onto the surrounding surface, and that methanol reacts quite facilely with the adsorbed oxygen atoms. In addition, the O species from O2 dissociation exhibits reactivity for the selective oxidation of methanol but not for CO. The TAP experiments also revealed that the surface of the npAu catalyst is saturated with adsorbed O under steady state reaction conditions, at least for the pulse reaction.

Ultracold collisions and reactions of vibrationally excited OH radicals with oxygen atoms

2011 ◽  
Vol 13 (42) ◽  
pp. 19067 ◽  
Author(s):  
Juan Carlos Juanes-Marcos ◽  
Goulven Quéméner ◽  
Brian K. Kendrick ◽  
Naduvalath Balakrishnan
Keyword(s):  
Oh Radicals ◽  
Vibrationally Excited ◽  
Ultracold Collisions ◽  
Oxygen Atoms

Production of Vibrationally Excited Carbon Monoxide by the Reaction of Oxygen Atoms with Acetylene, Methylacetylene, and Methane

1973 ◽  
Vol 51 (3) ◽  
pp. 451-455
Author(s):  
S. J. Arnold ◽  
G. H. Kimbell
Keyword(s):  
Carbon Monoxide ◽  
Electrical Discharge ◽  
Population Inversion ◽  
Continuous Wave ◽  
Microwave Discharge ◽  
Vibrationally Excited ◽  
Vibrational Population ◽  
Oxygen Atoms

Infrared chemiluminescence attributed to the first overtone of CO was observed when either C2H2 or was introduced into a stream of oxygen which had been passed through a microwave discharge. The addition of vibrationally cold CO to these systems was found to produce a vibrational population inversion in the chemically formed CO. CO first overtone emission was not observed when CH4 was introduced into a similar stream of oxygen unless the CH4 had been subjected to a microwave discharge. These observations are used to clarify the mechanisms governing the formation of CO in continuous wave air–helium–hydrocarbon electrical discharge lasers.

Kinetics of reactions involving CN emission IV. Study of the reactions of CN by electronic absorption spectroscopy

1968 ◽  
Vol 305 (1480) ◽  
pp. 107-123 ◽  
Keyword(s):  
Absorption Spectroscopy ◽  
Rate Constant ◽  
Electronic Absorption ◽  
Flow Reactor ◽  
Initial Step ◽  
Electronic Absorption Spectroscopy ◽  
Kinetics Of ◽  
Cn Radicals ◽  
Limiting Values ◽  
Oxygen Atoms

The kinetics of the reaction between oxygen atoms and cyanogen have been studied in a capacity flow reactor at temperatures between 570 and 687 °K. The concentration of CN radicals was measured by electronic absorption spectroscopy. This work confirms the previously proposed mechanism (part II). The initial step has a rate constant of k 1 = 2∙5 (± 0∙3) x 10 13 exp ( – 11000±2000/ RT ) cm 3 mole –1 s –1 . CN radicals are removed mainly by reactions (4) and (2) for which k 4 = 6∙3 (±3∙5) x 10 13 exp (–2400±700/ RT ) cm 3 mole –1 s –1 and k 2 = 4∙4 (±2∙0) x 10 12 cm 3 mole –1 s –1 . CN+O = CO+N, (4) CN+O 2 = NCO+O. (2) The rates of reaction of CN with NO and NH 3 were also measured; for CH 4 and H 2 limiting values were obtained.

Substituted homoallenyl aldehydes and their derivatives. Part 1: Homoallenyl aldehydes and protected hydrazones

2013 ◽  
Vol 67 (1) ◽  
Author(s):  
Juraj Galeta ◽  
Stanislav Man ◽  
Milan Potáček
Keyword(s):  
Triple Bond ◽  
Claisen Rearrangement ◽  
Initial Step ◽  
Sonogashira Coupling ◽  
Trans Isomers ◽  
Vinyl Ethers ◽  
X Ray ◽  
Cis And Trans Isomers ◽  
Cis And Trans ◽  
Sodium Amide

AbstractThe paper presents a simple synthesis of substituted propargyl vinyl ethers and their subsequent thermally-initiated Claisen rearrangement leading to various 3-substituted homoallenyl aldehydes. Several methods, including Sonogashira coupling, base-promoted substitution on the triple bond by sodium amide or butyllithium, and the preparation of substituted propargyl alcohols, were used in the initial step. Phosphate-protected homoallenyl aldehyde hydrazone derivatives were synthesised and fully characterised. The stereochemistry of 9-anthracene carbaldehyde hydrazone, which, surprisingly, afforded both cis and trans isomers, was established using X-ray analysis.

Sign in / Sign up

Export Citation Format

Share Document