排序方式: 共有27条查询结果,搜索用时 15 毫秒
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New ruthenium(II) complexes containing η6-arene-η1-pyrazole ligands were synthesized and characterized by elemental analysis and spectroscopic methods. In addition, the molecular structure of dichloro-3,5-dimethyl-1-(pentamethylbenzyl)-pyrazole–ruthenium(II), [Ru]L3b, was determined by X-ray diffraction studies. These complexes were applied in the transfer hydrogenation of acetophenone by isopropanol in the presence of potassium hydroxide. The activities of the catalysts were monitored by NMR. 相似文献
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A wide variety of alkoxymethyltrifluoroborate substrates were prepared via SN2 displacement of potassium bromomethyltrifluoroborate with various alkoxides in excellent yields. These alkoxymethyltrifluoroborates were effectively cross-coupled with several aryl chlorides. This method provides a unique dissonant disconnect that allows greater flexibility in the design of new and improved synthetic pathways. 相似文献
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Park YH Ahn HR Canturk B Jeon SI Lee S Kang H Molander GA Ham J 《Organic letters》2008,10(6):1215-1218
Potassium hydroxyaryl- and (hydroxyalkyl)aryltrifluoroborates have been prepared in a simple one-pot process from the corresponding hydroxy-substituted aryl halides in 51-98% yields through an in situ protection of the free hydroxyl group with t-BuLi. Also, we successfully performed a microwave-promoted Suzuki-Miyaura cross-coupling reaction of these substrates with aryl- and alkenyl bromides in the presence of 0.5 mol % of Pd(OAc)2 catalyst without ligands. 相似文献
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Parlak C Bilge M Kalaycı T Bardakçı B 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,79(5):1077-1083
FT-IR and Raman spectra of 5-o-tolyl-2-pentene (OTP) have been experimentally reported in the region of 4000-10 cm(-1) and 4000-100 cm(-1), respectively. The optimized geometric parameters, normal mode frequencies and corresponding vibrational assignments of cis and trans isomers of OTP (C12H16) have been theoretically examined by means of B3LYP hybrid density functional theory (DFT) method together with 6-31G(d) and 6-31++G(d,p) basis sets. Furthermore, reliable vibrational assignments have made on the basis of potential energy distribution (PED) calculated. Comparison between the experimental and theoretical results indicates that density functional B3LYP method is able to provide satisfactory results for predicting vibrational wavenumbers and trans isomer is supposed to be the most stable form of OTP molecule. 相似文献
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Gary A. Molander Prof. Belgin Canturk 《Angewandte Chemie (International ed. in English)》2009,48(49):9240-9261
Monocoordinated palladium catalysts derived from sterically hindered, electron‐rich phosphines or N‐heterocyclic carbenes have revolutionized the Suzuki–Miyaura coupling reaction. The emergence of organotrifluoroborates has provided important new perspectives for the organoboron component of these reactions. In combination, these two components prove to be extraordinarily powerful partners for cross‐coupling reactions. 相似文献
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Belgin Korkmaz 《Journal of Geometry》2003,77(1-2):108-128
A nullity condition for real contact manifolds is defined by Blair, Koufogiorgos and Papantoniu. Lately,
Boeckx classified such manifolds completely. In this paper, a nullity condition for complex contact manifolds is
defined as follows: take a complex contact manifold whose vertical space is annihilated by the curvature. Then,
apply an $\mathcal{H}$-homothetic deformation. In this way, we get a condition which is invariant under $\mathcal{H}$-homothetic
deformations. A complex contact manifold satisfying this condition is called a complex (,)-space. Some
curvature properties of complex (,)-spaces are studied and it is shown that, just as in the real case, the curvature
tensor of a complex (,)-space is completely determined. 相似文献
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An exploration into the scope of Suzuki aryl cross-coupling chemistry using derivatives of 1,1,2,2,9,9,10,10-octafluoro[2.2]paracyclophane is reported. The coupling of 4-iodo-1,1,2,2,9,9,10,10-octafluoro[2.2]paracyclophane with various aryl boronic acids and boronic acid pinacol esters was successful, with the exception of very sterically demanding systems, such as mesityl. The synthesis of the previously unreported 1,1,2,2,9,9,10,10-octafluoro[2.2]paracyclophanyl-4-boronic acid is described, together with various Suzuki aryl cross-coupling reactions of this new system. Using standard Suzuki methodology, it was possible to prepare dicyclophanes bearing two octafluoro[2.2]paracyclophane units separated by both one and two benzene rings. 相似文献