Photoisomerization of the boron trihalide complexes of eucarvone

1977 ◽  
Vol 55 (20) ◽  
pp. 3501-3508 ◽  
Author(s):  
Ronald F. Childs ◽  
Yee-Chee Hor
Keyword(s):  
Low Temperature ◽  
Product Distribution ◽  
Subsequent Recovery ◽  
Synthetic Utility ◽  
Primary Product Distribution ◽  
Low Degrees

The photoisomerization of the BF3, BCl3 and BBr3 complexes of eucarvone (2,6,6-trimethylcyclohepta-2,4-dienone), 1, have been examined. Irradiation of these zwitterions at low temperature gave, after subsequent recovery of decomplexed materials, 3,7,7-trimethylbicyclo-[4.1.0]hept-2-en-4-one, 2, 2-methyl-5-isopropylphenol, 3, 2-methyl-6-isopropylphenol, 4, dehydrocamphor, 5, and carvone, 6. In the case of 1•BF3 and 1•BCl3 the initial photoproducts were shown to be the complexes of 2, 3, 4, and 5. The complexes of 6 were shown to arise from a secondary photoisomerization of 2•BX3. It was not possible to establish the primary product distribution, obtained from 1•BBr3 as further photoisomerization of 2•BBr3 occurred even at very low degrees of conversion. The mechanisms and synthetic utility of these reactions is discussed.

Low Temperature α -Irradiation of White Tin and Subsequent Recovery

1971 ◽  
Vol 43 (2) ◽  
pp. K149-K151 ◽  
Author(s):  
G. Von Heyden ◽  
L. Stais ◽  
J. Nihoul
Keyword(s):  
Low Temperature ◽  
Subsequent Recovery

scholarly journals Low-Temperature Damage and Subsequent Recovery of fab1 Mutant Arabidopsis Exposed to 2[deg]C

1997 ◽  
Vol 113 (2) ◽  
pp. 347-356 ◽  
Author(s):  
J. Wu ◽  
J. Lightner ◽  
N. Warwick ◽  
J. Browse
Keyword(s):  
Low Temperature ◽  
Subsequent Recovery ◽  
Temperature Damage

Fischer–Tropsch Synthesis: Using Deuterium as a Tool to Investigate Primary Product Distribution

2013 ◽  
Vol 144 (3) ◽  
pp. 524-530 ◽  
Author(s):  
Jia Yang ◽  
Wilson D. Shafer ◽  
Venkat Ramana Rao Pendyala ◽  
Gary Jacobs ◽  
De Chen ◽  
...  
Keyword(s):  
Product Distribution ◽  
Tropsch Synthesis ◽  
Fischer Tropsch ◽  
Fischer Tropsch Synthesis ◽  
Primary Product Distribution

Fluorination of Uranium Metal to UF3 and UF4 by Nitrogen Trifluoride: Evidence for Elusive UF2

2010 ◽  
Vol 1264 ◽  
Author(s):  
Bruce K McNamara ◽  
Randall Scheele ◽  
Andrew M Casella ◽  
Anne E Kozelisky ◽  
Doinita Neiner
Keyword(s):  
Low Temperature ◽  
Product Distribution ◽  
Nitrogen Trifluoride ◽  
Uranium Metal ◽  
Metal Catalyzed

AbstractWe have recently found that uranium and plutonium metals will react with nitrogen trifluoride (NF3) at temperatures below 120°C. These are the first reported instances of such low temperature fluorination reactions using NF3 and implicate metal catalyzed dissociation of the NF3 bond. We additionally present preliminary evidences for a surface mediated product distribution. Reaction of uranium metal with NF3 promotes products that are apparently determined by the concentration of the fluorinating reagent between temperatures of 60 to 120°C.

Recent advances in reactors for low-temperature Fischer-Tropsch synthesis: process intensification perspective

2015 ◽  
Vol 31 (3) ◽  
Author(s):  
Samrand Saeidi ◽  
Maryam Khoshtinat Nikoo ◽  
Azadeh Mirvakili ◽  
Samaneh Bahrani ◽  
Nor Aishah Saidina Amin ◽  
...  
Keyword(s):  
Low Temperature ◽  
Fixed Bed ◽  
Process Intensification ◽  
Product Distribution ◽  
Membrane Reactors ◽  
Synthesis Process ◽  
Microchannel Reactor ◽  
Fischer Tropsch ◽  
Mixing Properties ◽  
Reactor Technology

AbstractThe low-temperature Fischer-Tropsch (LTFT) process aims to produce heavy cuts such as wax and diesel. For many years, there have been studies and improvements on the LTFT process to make the existing reactors more efficient. Recent studies have proposed innovative configurations such as monolithic loop and membrane reactors as well as microchannel reactor, which improved the performance of LTFT synthesis. This persuades us to update the existing knowledge about the available reactors. Some fundamental features of the current reactors, which belong to the classes of conventional reactors (fixed-bed reactors and slurry reactors) and innovative reactors, are discussed to assist the selection of the most efficient reactors specifically for heavy-cuts production. Published experimental and theoretical works with respect to developments in reactor technology and significant advances in catalysis (such as using structured packing, foams, and knitted wire as catalyst supports due to their excellent radial mixing properties) of the FT process are analyzed and discussed. Consequently, it is shown that the LTFT innovative reactors have higher CO conversions and selectivity of desired heavy cuts. Furthermore, the place of innovative reactors among conventional reactors in terms of effective process parameters on the product distribution has been estimated.

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