- Conformational characteristics of aliphatic diesters derived from fluorinated diacids
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A comparative study of the polarity and conformational characteristics of diethyl hexafluoroglutarate (DEFG) and its hydrogenated diester counterpart, diethyl glutarate (DEG), is reported. The value at 30°C of the mean-square dipole moment 〈μ2〉 of the latter compound, 5.26 D2, is nearly 2 times larger the value of this quantity for the fluorinated diester, which amounts to 12.1 D2 at the same temperature. Values of the conformational energies associated with the rotational states about the skeletal bonds of the acid residue were calculated by combining molecular mechanics with the critical interpretation of the mean-square dipole moment of these compounds, finding that the rotational populations about the different skeletal bonds are similar in both molecules. The evaluation of 〈μ2〉 as a function of the conformational energies indicates that the experimental results are reproduced assuming that the conformation in which the C=O* group eclipses the Cα-Cβ bond in the CβCαC*(O*)O residue is less stable than the alternative conformation in which the carbonyl group eclipses the Cα-F (or Cα- H) bond. The analysis suggests that the high polarity exhibited by DEFG, in comparison with that of DEG, arises from differences in the orientation and the modulus of the dipoles in both compounds rather than from differences in their conformational characteristics.
- Reis-Nunes, Regina C.,Riande, Evaristo,Chavez, Nelson C.,Guzman, Julio
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- Method for preparing fluorine-containing dihydric alcohol from fluorine-containing cycloolefin
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The invention discloses a method for preparing fluorine-containing dihydric alcohol from fluorine-containing cycloolefin. The method comprises the following steps: oxidizing fluorine-containing cycloolefin serving as a raw material by using an oxidizing agent and treating the fluorine-containing cycloolefin by using a strong alkali to generate a solid mixed salt containing corresponding fluorine-containing dicarboxylate, and then generating corresponding fluorine-containing binary acyl chloride under the action of an acylating chlorination reagent; and finally, enabling the fluorine-containing binary acyl chloride and a reducing agent to be subjected to a reduction reaction under the action of a solvent and a catalyst to obtain the corresponding fluorine-containing dihydric alcohol. The specific organic solvent and catalyst are adopted, and other conditions are matched, so that the fluorine-containing cycloolefin can be effectively promoted to generate corresponding fluorine-containing dihydric alcohol with high efficiency and high yield. The method has the advantages of easily available raw materials, simple process, convenience in operation, low cost and the like, and is suitable for large-scale production of fluorine-containing dihydric alcohol.
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Paragraph 0060
(2021/07/01)
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- Biphenyl-pyrazolecarboxamide compounds
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The present invention relates to biphenyl-pyrazole compounds and in particular biphenyl-pyrazolecarboxamides. The invention further provides compositions comprising a compound of this invention and the use of such compositions in methods of treating diseases and conditions beneficially treated by antagonism or inverse agonism of the CB1 receptor, such as obesity, smoking cessation, and normalization of blood lipid composition.
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Page/Page column 26; 27
(2008/06/13)
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- A new synthetic route to symmetrical photochromic diarylperfluorocyclopentenes
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Symmetrical and photochromic diarylperfluorocyclopentene has been prepared by reaction of 3-lithio-5-chloro-2-methylthiophene with the ethyl ester of hexafluoroglutaric acid, followed by ring closure via a McMurry coupling. Compound 7 is a versatile intermediate for the development of photochromic materials.
- Lucas, Linda N.,Van Esch, Jan,Kellogg, Richard M.,Feringa, Ben L.
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p. 1775 - 1778
(2007/10/03)
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