Product Isomer Distribution in the Sequential Functionalization of Cyclic PIII 2 N2 Frameworks

2017 ◽  
Vol 2017 (35) ◽  
pp. 4123-4130 ◽  
Author(s):  
Deependra Bawari ◽  
Billa Prashanth ◽  
Kuldeep Jaiswal ◽  
Angshuman Roy Choudhury ◽  
Sanjay Singh
Keyword(s):  
Isomer Distribution

Synthesis and cytotoxicity of deoxyadenosine analogs: isomer distribution in the sodium salt glycosylation of 2,6-disubstituted purines

1990 ◽  
Vol 33 (6) ◽  
pp. 1683-1687 ◽  
Author(s):  
Zygmunt Kazimierczuk ◽  
Juhani Vilpo ◽  
Catherine Hildebrand ◽  
George Wright
Keyword(s):  
Sodium Salt ◽  
Isomer Distribution

Oxidation of hydrocarbons in the liquid phase: n-dodecane in a borosilicate glass chamber at 200 °C

1969 ◽  
Vol 47 (22) ◽  
pp. 4175-4182 ◽  
Author(s):  
B. D. Boss ◽  
R. N. Hazlett
Keyword(s):  
Liquid Phase ◽  
Borosilicate Glass ◽  
Current Knowledge ◽  
Reaction Chamber ◽  
Cyclic Ethers ◽  
Reaction Products ◽  
Isomer Distribution ◽  
Oxidation Of Hydrocarbons ◽  
Volatile Products ◽  
Rate Of Reaction

The 5-h oxidation of n-dodecane at 200 °C by air at 1 atm is reported for experiments in a borosilicate glass reaction chamber equipped with a gas bubbler. The rate of reaction was limited by the rate of oxygen diffusion from the gas phase due to the rapid reaction of dissolved oxygen. The reaction products were analyzed in aliquots taken periodically from the reaction chamber. Chemical analyses, gas–liquid phase chromatography (g.l.p.c.), tandem g.l.p.c.-mass spectroscopy, infrared, and ultraviolet were used to identify products accounting for 98% of the oxygen reacted. The isomer distribution of the dodecenes, dodecanols, and dodecanones formed, as well as the distribution of carboxylic acids, were determined. Three classes of intramolecular reaction products, cyclic ethers, cyclic hydrocarbons, and lactones, were detected. Many volatile products were detected. A filterable precipitate obtained after 10 h of oxidation was studied using infrared attenuated total reflectance techniques. A reaction mechanism is discussed based on current knowledge of other systems, the products identified, and the stoichiometry of the reaction.

Influence of Organic Structure Directing Agent Isomer Distribution on the Synthesis of SSZ-39

2015 ◽  
Vol 27 (7) ◽  
pp. 2695-2702 ◽  
Author(s):  
Michiel Dusselier ◽  
Joel E. Schmidt ◽  
Roger Moulton ◽  
Barry Haymore ◽  
Mark Hellums ◽  
...  
Keyword(s):  
Structure Directing Agent ◽  
Organic Structure ◽  
Isomer Distribution

scholarly journals Rapid hydrolysis of tertiary isoprene nitrate efficiently removes NOx from the atmosphere

2020 ◽  
Vol 117 (52) ◽  
pp. 33011-33016
Author(s):  
Krystal T. Vasquez ◽  
John D. Crounse ◽  
Benjamin C. Schulze ◽  
Kelvin H. Bates ◽  
Alexander P. Teng ◽  
...  
Keyword(s):  
Transport Model ◽  
Deuterium Oxide ◽  
Ambient Air ◽  
Water Volume ◽  
Isomer Ratio ◽  
Atmospheric Measurements ◽  
Laboratory Findings ◽  
Loss Process ◽  
Isomer Distribution ◽  
Hydrolysis Of

The formation of a suite of isoprene-derived hydroxy nitrate (IHN) isomers during the OH-initiated oxidation of isoprene affects both the concentration and distribution of nitrogen oxide free radicals (NOx). Experiments performed in an atmospheric simulation chamber suggest that the lifetime of the most abundant isomer, 1,2-IHN, is shortened significantly by a water-mediated process (leading to nitric acid formation), while the lifetime of a similar isomer, 4,3-IHN, is not. Consistent with these chamber studies, NMR kinetic experiments constrain the 1,2-IHN hydrolysis lifetime to less than 10 s in deuterium oxide (D2O) at 298 K, whereas the 4,3-IHN isomer has been observed to hydrolyze much less efficiently. These laboratory findings are used to interpret observations of the IHN isomer distribution in ambient air. The IHN isomer ratio (1,2-IHN to 4,3-IHN) in a high NOx environment decreases rapidly in the afternoon, which is not explained using known gas-phase chemistry. When simulated with an observationally constrained model, we find that an additional loss process for the 1,2-IHN isomer with a time constant of about 6 h best explains our atmospheric measurements. Using estimates for 1,2-IHN Henry’s law constant and atmospheric liquid water volume, we show that condensed-phase hydrolysis of 1,2-IHN can account for this loss process. Simulations from a global chemistry transport model show that the hydrolysis of 1,2-IHN accounts for a substantial fraction of NOx lost (and HNO3 produced), resulting in large impacts on oxidant formation, especially over forested regions.

Sign in / Sign up

Export Citation Format

Share Document