RADIATION CHEMISTRY OF CYCLOHEXANE: IV. PRIMARY PRODUCT YIELDS IN THE IRRADIATION OF CYCLOHEXANE

1961 ◽  
Vol 39 (12) ◽  
pp. 2381-2388 ◽  
Author(s):  
P. J. Dyne ◽  
J. A. Stone
Keyword(s):  
Radiation Chemistry ◽  
Secondary Reaction ◽  
Reaction Products ◽  
Primary Reaction ◽  
Product Yields ◽  
Primary Products ◽  
High Irradiation

The radiolysis of cyclohexane has been studied at low total doses and initial G values have been determined. Ninety-nine per cent of the evolved hydrogen has been accounted for in hydrogen-deficient products. Cyclohexene, bicyclohexyl, and cyclohexyl-hexene-1 have been identified as primary reaction products. Cyclohexyl-cyclohexene has been identified as a secondary reaction product. The use of high irradiation doses has been shown to lead to decreases in the initial G values of all primary products.

scholarly journals Study of the Synchrotron Photoionization Oxidation of Alpha-Angelica Lactone (AAL) Initiated by O(3P) at 298, 550, and 700 K

Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 4070
Author(s):  
Golbon Rezaei ◽  
Giovanni Meloni
Keyword(s):  
Atomic Oxygen ◽  
Fossil Fuels ◽  
Reaction Products ◽  
Photoionization Mass Spectrometry ◽  
Natural Substances ◽  
Primary Products ◽  
Major Reaction ◽  
Angelica Lactone ◽  
Significant Attention

In recent years, biofuels have been receiving significant attention because of their potential for decreasing carbon emissions and providing a long-term renewable solution to unsustainable fossil fuels. Currently, lactones are some of the alternatives being produced. Many lactones occur in a range of natural substances and have many advantages over bioethanol. In this study, the oxidation of alpha-angelica lactone initiated by ground-state atomic oxygen, O(3P), was studied at 298, 550, and 700 K using synchrotron radiation coupled with multiplexed photoionization mass spectrometry at the Lawrence Berkeley National Lab (LBNL). Photoionization spectra and kinetic time traces were measured to identify the primary products. Ketene, acetaldehyde, methyl vinyl ketone, methylglyoxal, dimethyl glyoxal, and 5-methyl-2,4-furandione were characterized as major reaction products, with ketene being the most abundant at all three temperatures. Possible reaction pathways for the formation of the observed primary products were computed using the CBS–QB3 composite method.

Sulfur Linkage in Vulcanized Rubber. Reaction of Methyl Iodide with Sulfur Compounds

1949 ◽  
Vol 22 (1) ◽  
pp. 1-7
Author(s):  
M. L. Selker
Keyword(s):  
Methyl Iodide ◽  
Room Temperature ◽  
Sulfur Compounds ◽  
Point Of View ◽  
Secondary Reaction ◽  
Reaction Products ◽  
Sulfide Sulfur ◽  
Vulcanized Rubber ◽  
Allyl Sulfide

Abstract The work described here is an extension of the study of the reaction of methyl iodide with sulfur compounds originally begun with the purpose of using such data in determining the sulfur linkage in vulcanized rubber. A previous paper dealt with the reactions of methyl iodide with propanethiol, propyl sulfide, propyl disulfide, allyl sulfide, and thiophene. This article adds to the list, n-butyl methallyl sulfide, allyl disulfide, allyl tetrasulfide, n-propyl tetrasulfide, and trithiane. The removal of combined sulfur from vulcanized rubber as trimethylsulfonium iodide on treatment with methyl iodide at room temperature was persuasive evidence of the presence of sulfide sulfur linked to allylic type residues. The evidence offered, however, did not constitute exclusive proof because it was not known whether still other types of sulfur linkage would also yield trimethylsulfonium iodide. To shed more light on this question, the sulfur linkages most likely to occur in vulcanizates—the allyl-alkyl monosulfide, diallyl and dialkyl di- and polysulfide—were investigated. The trithiane reaction is of interest mostly from the point of view of the reaction of overcured stocks or secondary reaction products stemming from the original polysulfides. The reactions were carried out using the method described in a previous paper.

The gaseous oxidation of 2-methyl-but-2-ene. I. Kinetic and analytical studies

1961 ◽  
Vol 262 (1310) ◽  
pp. 318-327 ◽  
Keyword(s):  
Double Bond ◽  
Methyl Alcohol ◽  
Initial Pressure ◽  
Pressure Increase ◽  
Reaction Products ◽  
Initial Attack ◽  
Primary Reaction ◽  
Slow Combustion ◽  
Propyl Ketone ◽  
Parallel Fashion

In the slow combustion of 2-methyl-but-2-ene at ca . 250 °C, an initial pressure decrease, which represents the formation of peroxidic intermediates, is followed by an autocatalytic pressure increase during which little olefin is consumed and the main processes are break ­ down and further oxidation of primary reaction products. Acetone and acetaldehyde are the principal early non-peroxidic products and these are formed initially in equivalent quantities and in closely parallel fashion. Methyl iso propyl ketone is produced in somewhat smaller amounts and methyl alcohol, which appears comparatively late in the reaction, probably arises from the oxidation of acetaldehyde. The results suggest that the predominant mode of initial attack of the olefin is addition of oxygen to the double bond followed by decomposition of the resulting cyclic peroxides, although some hydroperoxylation also occurs.

Cyclopropylcarbinyl-oxo-carbonium Ions. Part VI. Synthesis and Chemistry of an Epimeric Pair of Homoallyl Iodides (3-Iodomethyl Glycals)

1972 ◽  
Vol 50 (18) ◽  
pp. 2919-2927 ◽  
Author(s):  
Bert Fraser-Reid ◽  
Bruno Radatus
Keyword(s):  
Transition State ◽  
Major Product ◽  
Alternative Route ◽  
Allylic Rearrangement ◽  
Reaction Products ◽  
Primary Reaction ◽  
Methylene Iodide ◽  
Carbonium Ions ◽  
Synthetic Sequence ◽  
Zinc Iodide

The homoallyl iodide 4,6-O-benzylidene-1,2,3-trideoxy-D-ribo-hex-1-enopyranose, 4, is the second major product from Simmons–Smith reaction of methyl 4,6-O-benzylidene-2,3-dideoxy-α-D-erythro-hex-2-enopy-ranoside, 6α. The major product is the cyclopropyl glycoside 7α, which when treated separately with the Simmons–Smith reagents furnishes an 85% yield of 4. The mechanism of this transformation is investigated. It is not simply a Lewis-catalyzed iodinolysis since zinc iodide in a variety of solvents does not convert 7α to 4. Methylene iodide is essential, as is the organo-zincate complex, operative in Simmons–Smith reactions.The 3-epimer of the homoallyl iodide 4, i.e. 4,6-O-benzylidene-1,2,3-trideoxy-D-arbino-hex-1-enopyranose, 5, is produced in only 0.9% yield in the methylenation of the anomeric olefinic glycoside, 6β. The low yield is attributable to the extensive anomerization experienced by 6β itself, and by the primary reaction products. This leads to a plethora of compounds including both epimeric homoallyl iodides 4 and 5.In order to get it all together, the homoallyl iodide 4 is transformed into its epimer 5 by an unambiguous synthetic sequence. Some of the intermediates in this sequence are polyfunctional molecules of considerable synthetic potential.The possibility of an alternative route to compound 4 directly from the olefinic glycoside 6α is discussed. Coordination of the methoxyl oxygen of 6α to the organo-zincate complex could achieve an ideal SNi transition state in which [Formula: see text] is delivered at C-3 with synchronous departure of the methoxyl group. This mechanism, called the "reverse" allylic rearrangement for reasons outlined in the text, is discussed.

Rubber. XVIII. Various Ozonides of Rubber and the Problem of the Existence of the Primary Ozonides of Harries

1938 ◽  
Vol 11 (1) ◽  
pp. 7-31
Author(s):  
Rudolf Pummerer ◽  
Hermann Richtzenhain
Keyword(s):  
Carbon Chain ◽  
Mesityl Oxide ◽  
Addition Reactions ◽  
Reaction Products ◽  
Primary Reaction ◽  
Carbon Chains ◽  
Fundamental Objection ◽  
Great Stress ◽  
Valuable Service ◽  
General Method

Abstract A permanently valuable service was rendered by Harries when he introduced the ozone cleavage of unsaturated compounds as a general method of investigation in organic chemistry. By analogy with other addition reactions of double bonded carbon atoms he derived the formula (a) for the ozonides which are first formed, but to support the existence of which he was able to obtain only scant experimental data. Harries relied above all on two observations, first, that mesityl oxide ozonide reverts to mesityl oxide when heated by itself, and, secondly, that fumaric acid is supposed to combine loosely with ozone and then readily split off again. Both of these suppositions have remained undisputed up to the present time. Harries reported that it was not possible, with any of a wide variety of reducing agents, to reduce the ozonides to the original compounds or to 1,2-glycols, as would be expected from their structure. Staudinger has laid great stress on this fundamental objection, and he considers that most ozonides have an isoözinide formula, as shown by formula (b) above, in which the carbon chain is already ruptured, so that by reduction only the usual types of cleavage products rather than glycols with intact carbon chains can be formed, as has been found experimentally. Staudinger assumed that the primary reaction products of treatment with ozone are molozonides containing the group:

On the application of RRKM theory to the unimolecular isomerization of monofluorocyclopropane: a reaction with multiple fall-off characteristics?

1978 ◽  
Vol 56 (1) ◽  
pp. 29-31 ◽  
Author(s):  
Michael C. Flowers
Keyword(s):  
Pressure Dependence ◽  
Reaction Products ◽  
Arrhenius Parameters ◽  
Rrkm Theory ◽  
Product Yields ◽  
Cis And Trans

Monofluorocyclopropane isomerizes at 475 °C to form cis- and trans-1-fluoropropene, 2-fluoropropene, and 3-fluoropropene. The relative amounts of these products formed are pressure dependent. It is shown that, using the previously determined Arrhenius parameters for the formation of each product, RRKM theory does account satisfactorily for the pressure dependence of the product yields for all the reaction products.

Reaction products of diorganotin(IV) oxides, R2SnO, with nitric acid. Part 2 – R = n-butyl and t-butyl

2014 ◽  
Vol 92 (6) ◽  
pp. 484-495 ◽  
Author(s):  
Hans Reuter ◽  
Martin Reichelt
Keyword(s):  
Nitric Acid ◽  
Reaction Products ◽  
X Ray Diffraction ◽  
Primary Reaction ◽  
Dimeric Molecule ◽  
X Ray ◽  
Trigonal Bipyramidal ◽  
Solvent Molecules ◽  
Hydroxide Hydrate ◽  
Hydrogen Bonded

The reaction of diorganotin(IV) oxides, R2SnO with R = n-butyl and t-butyl, with nitric acid in different stoichiometric ratios resulted in the formation of different products depending on the organic groups attached to the tin atom: the diorganotin(IV) dinitrate dihydrates, n-Bu2Sn(NO3)2·2H2O (2d) and t-Bu2Sn(NO3)2·2H2O (2e), the mixed diorganotin(IV) nitrate methoxide oxide n-Bu2Sn(NO3)(n-Bu2SnOMe)O (6), and the diorganotin(IV) nitrate hydroxide hydrate t-Bu2Sn(NO3)(OH)·H2O = [t-Bu2Sn(OH)(H2O)][NO3] (7). On examination of the solubility of the primary reaction products in different solvents, the three additional compounds t-Bu2Sn(NO3)(OH)·DMSO (8), t-Bu2Sn(NO3)(OH)·THF, and 2-t-Bu2Sn(NO3)(OH)·DMF = [t-Bu2Sn(OH)dmf]2[NO3]2·[t-Bu2Sn(NO3)OH]2 (9) could be isolated. All compounds have been structurally characterized by single crystal X-ray diffraction (primary results for 7) with special attention paid to dimensionality (2d and 2c = monomeric, hydrogen bonded molecules; 6 = dimeric molecules of ladder-type structure; 7 = dimeric cation; 8 = dimeric molecule with hydrogen bonded solvent molecules; 9 = both components dimeric), tin coordination (6, 7, 8, and 9 = trigonal bipyramidal; 2d and 2e = eightfold), and nitrate bonding modes (7 and 9 = isolated, hydrogen bonded; 6, 8, and 9 (component 2) = monodentate; 2d and 2e = symmetrical bidentate), the latter one being analyzed using both Sn–O and N–O distances.

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