- Thermal transformation of monoterpenes within thionin-supported zeolite Na-Y. Acid-catalyzed or electron transfer-induced?
-
Several monoterpenes (monocyclic, bicyclic or acyclic) isomerize and finally transform to p-cymene in the dark upon loading within thionin-supported zeolite Na-Y. The same reactions occur in Na-Y dried under the same conditions as thionin/Na-Y. It is postulated that the thermal treatment of Na-Y generates 'electron holes' (probably acidic sites). The transformation of monoterpenes occurs more likely via an electron transfer-induced reaction subordinated to the occurrence of the acidic sites. The radical cation of the more thermodynamically stable monoterpene, α-terpinene, eventually dehydrogenates to p-cymene. For comparison, the same reactions were performed within methyl viologen-supported Na-Y. Copyright
- Stratakis, Manolis,Stavroulakis, Manolis,Sofikiti, Nikoletta
-
-
Read Online
- HETEROGENEOUS HYDROGENATION OF 3,7,7-TRIMETHYLCYCLOHEPTA-1,3,5-TRIENE
-
It has been shown that the intermediate products of the hydrogenation of 3,7,7-trimethylcyclohepta-1,3,5-triene on platinum black are 2- and 3-carenes, in addition to olefins and dienes of the 1,1,4-trimethylcycloheptane series.The final hydrogenation products contains 96percent of 1,1,4-trimethylcycloheptane and 4percent of carenes.
- Manukov, E. N.,Chuiko, V. A.
-
-
Read Online
- Fine particle and gaseous emission rates from residential wood combustion
-
Residential wood combustion emissions were analyzed to determine emission rates and to develop chemical emissions profiles that represent the appliances and woods typically used in wood-burning-communities. Over 350 elements, inorganic compounds, and organic compounds were quantified. A range of 4-9 g/kg dry fuel of particulate matter(a dilution stack sampler equipped with a 2.5-μm particle selective cyclone. Emissions were diluted 20-70 times, cooled to ambient temperature, and allowed 80 s for condensation prior to collection. Wood type, wood moisture, burn rate, and fuel load were varied for different experiments. Fine particle and se mivolatile organic compounds were collected on filter/PUF/XAD/PUF cartridges. Inorganic samples and mass were collected on Teflon and quartz filters. Volatile organic carbon compounds were trapped with Tenax (C8- C20), canister (C2-C12), and 2,4-dinitrophenylhydrazine impregnated cartridges (carbonyl compounds). Analysis of particle and semivolatile organic species was conducted by gas chromatography/mass spectrometry. Teflon filters were analyzed for mass by gravimetry, trace elements were analyzed by X-ray fluorescence and ammonium was analyzed by automated colorimetry. Quartz filters were analyzed for organic and elemental carbon by thermal/optical reflectance, and forts were analyzed by ion chromatography. Select quartz filters were analyzed by accelerator mass spectrometry for carbon-12 and carbon-14 abundance. Canister and Tenax samples were analyzed by gas chromatography with a flame ionization detector, and carbonyl compounds were analyzed by high-performance liquid chromatography. Residential wood combustion emissions were analyzed to determine emission rates and to develop chemical emissions profiles that represent the appliances and woods typically used in wood-burning communities. Over 350 elements, inorganic compounds, and organic compounds were quantified. A range of 4-9 g/kg dry fuel of particulate matter (a dilution stack sampler equipped with a 2.5-μm particle selective cyclone. Emissions were diluted 20-70 times, cooled to ambient temperature, and allowed 80 s for condensation prior to collection. Wood type, wood moisture, burn rate, and fuel load were varied for different experiments. Fine particle and semivolatile organic compounds were collected on filter/PUF/XAD/PUF cartridges. Inorganic samples and mass were collected on Teflon and quartz filters. Volatile organic carbon compounds were trapped with Tenax (C8-C20), canister (C2-C12), and 2,4-dinitrophenylhydrazine impregnated cartridges (carbonyl compounds). Analysis of particle and semivolatile organic species was conducted by gas chromatography/mass spectrometry. Teflon filters were analyzed for mass by gravimetry, trace elements were analyzed by X-ray fluorescence, and ammonium was analyzed by automated colorimetry. Quartz filters were analyzed for organic and elemental carbon by thermal/optical reflectance, and ions were analyzed by ion chromatography. Select quartz filters were analyzed by accelerator mass spectrometry for carbon-12 and carbon-14 abundance. Canister and Tenax samples were analyzed by gas chromatography with a flame ionization detector, and carbonyl compounds were analyzed by high-performance liquid chromatography.
- Mcdonald, Jacob D.,Zielinska, Barbara,Fujita, Eric M.,Sagebiel, John C.,Chow, Judith C.,Watson, John G.
-
p. 2080 - 2091
(2007/10/03)
-
- Transformations of 3-carene oxide at rhenium-containing catalysts
-
The transformations of 3-carene oxide at rhenium-containing catalysts were studied.The introduction of rhenium into the catalytic system significantly increases the reaction rate and leads to the formation of compounds not previously encountered in the products from the isomerization of 3-carene oxide, i.e., 3-carene, 3(10),4-caradiene, 3,3,6-trimethylcycloheptanone, and 3-caren-10-ol.
- Manukov, E. N.,Bazhina, G. N.
-
p. 106 - 110
(2007/10/02)
-
- Diels-Alder Reactions of β-Stannyl Enones: Synthesis of Δ3-Carene, Isosesquicarene, and Other Bicyclohept-3-enes
-
Various trans-β-stannyl enones, trans-3-(tributylstannyl)-2-propenal, and trans-ethyl 3-(tributylstannyl)-2-propenoate were prepared and found to readily undergo Diels-Alder reactions with 1,3-dienes.The cycloaddition occurs with maintenance of trans tin/
- Johnson, Carl R.,Kadow, John F.
-
p. 1493 - 1500
(2007/10/02)
-
- TRANSFORMATIONS OF 4-HYDROXYMETHYL-2-CARENE OVER POTASSIUM HYDROXIDE
-
The dehydration of 4-hydroxymethyl-2-carene over potassium hydroxide at 250 deg C, which leads to the formation of 4-methyl-3(10),4-caradiene and 3,4,7,7-tetramethyl-1,3,5-cycloheptatriene, was investigated.The dehydration is accompanied by a small degree
- Manukov, E. N.,Vyglazov, O. G.,Chuiko, V. A.,Shingel', I. A.
-
p. 1912 - 1914
(2007/10/02)
-
- THE REACTION OF HYPOCHLOROUS ACID WITH OLEFINS. A CONVENIENT SYNTHESYS OF ALLYLIC CHLORIDES
-
The reaction of HOCl with more highly substituted olefins in methylene chloride affords allylic chlorides in 60-80percent isolated yields.The utility of the reaction is illustrated with the synthesis of Rose oxide and α-monoterpenes.
- Hegde, Shridhar G.,Vogel, Martin K.,Saddler, John,Hrinyo, Tanya,Rockwell, Ned,et al.
-
p. 441 - 444
(2007/10/02)
-