- 2-aryl-6-polyfluoroalkyl-4-pyrones as promising rf-building-blocks: Synthesis and application for construction of fluorinated azaheterocycles
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A convenient and general method for the direct synthesis of 2-aryl-6-(trifluoromethyl)-4-pyrones and 2-aryl-5-bromo-6-(trifluoromethyl)-4-pyrones has been developed on the basis of one-pot oxidative cyclization of (E)-6-aryl-1,1,1-trifluorohex-5-ene-2,4-diones via a bromination/dehy-drobromination approach. This strategy was also applied for the preparation of 2-phenyl-6-polyfluoroalkyl-4-pyrones and their 5-bromo derivatives. Conditions of chemoselective enediones bromination were found and the key intermediates of the cyclization of bromo-derivatives to 4-pyrones were characterized. Synthetic application of the prepared 4-pyrones has been demonstrated for the construction of biologically important CF3-bearing azaheterocycles, such as pyra-zoles, pyridones, and triazoles.
- Mysik, Daria K.,Naumov, Nikita A.,Nigamatova, Diana I.,Obydennov, Dmitrii L.,Sosnovskikh, Vyacheslav Y.,Usachev, Sergey A.
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- Synthesis and characterization of the titanium complexes bearing two regioisomeric trifluoromethyl-containing enaminoketonato ligands and their behavior in ethylene polymerization
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A series of new titanium complexes bearing two regioisomeric trifluoromethyl-containing enaminoketonato ligands (3a-h and 6a-h), [PhNCRCHC(CF3)O]2TiCl2 (3a, R = Me; 3b, R = n-C5H11; 3c, R = i-Pr; 3d, R = Cy; 3e, R = t-Bu; 3f, R = CHCHPh; 3g, R = Et; 3h, R = n-C11H23) and [PhNC(CF 3)CHC(R)O]2TiCl2 (6a, R = Ph; 6b, R = n-C 5H11; 6c, R = i-Pr; 6d, R = Cy; 6e, R = t-Bu; 6f, R = CHCHPh; 6g, R = CHPh2; 6h, R = CF3) have been synthesized and characterized. X-ray crystal structures analyses suggest that complexes 3c-e and 6c-d all adopt a distorted octahedral geometry around the titanium center. Complexes 3c, 3d and 6c display a cis-configuration of the two chlorine atoms around the titanium center, while complex 6d shows a trans-configuration of the two chlorine atoms. Especially, the configurational isomers (cis and trans) of complex 3e were identified both in solution and in the solid state by NMR and X-ray analyses. With modified methylaluminoxane as a cocatalyst, all the complexes are active towards ethylene polymerization, and produce high molecular weight polymers. With the variation of the relative position of the imino group and the trifluoromethyl group of the β-enaminoketonato ligands, the polymerization behavior of the catalysts changed remarkably. It is observed that the substituent directly joined to the carbonyl in the ligands plays an important role for both the catalytic activities and the properties of the polymers produced. The Royal Society of Chemistry 2009.
- Ye, Wei-Ping,Mu, Hong-Liang,Shi, Xin-Cui,Cheng, Yan-Xiang,Li, Yue-Sheng
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experimental part
p. 9452 - 9465
(2010/03/04)
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- Pyrazoles for the treatment of obesity and other CNS disorders
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This invention relates to compounds having pharmacological activity, to compositions containing these compounds, and to a method of treatment employing the compounds and compositions. More particularly, this invention concerns certain pyrazole derivatives, their salts and solvates. These compounds have H3 histamine receptor binding activity. This invention also relates to pharmaceutical compositions containing these compounds and to a method of treating disorders in which histamine H3 receptor modulation is beneficial.
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Page/Page column 10
(2010/11/28)
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- Synthesis of polyfluoroalkyl-containing dienones
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Previously unknown β-fluoroalkyl-α,β,α',β'-dienones were synthesized by dehydration of β-hydroxy-β-fluoroalkyl-α',β'-enones.
- Pashkevick,Khomutov
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p. 2169 - 2171
(2007/10/03)
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