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221.
合成了 2 个丁二酮肟有机锡化合物:双(三(2-甲基-2-苯基丙基)锡)丁二酮肟配合物(C6H5C(CH3)2CH2)3Sn(ON=C(CH3)C(CH3)=NO)Sn(CH2C(CH3)2C6H5)3 (1)和二苄基锡氧氯丁二酮肟多核配合物[μ3-O-((C6H5CH2)2Sn)2(ON=C(CH3)C(CH3)=NOH)(O)Cl]2(2)。通过元素分析、红外光谱、核磁共振(1H、13C、119Sn)、差热分析和单晶X射线衍射对配合物进行了结构表征,对其结构进行量子化学从头计算,并进行了体外抗癌活性研究。结果显示:配合物1为通过配体丁二酮肟桥联的双锡核中心对称分子,锡原子均为四配位的畸变四面体构型;配合物2为通过氧原子和丁二酮肟配体桥联的四锡核中心对称多环聚合结构,锡原子分别为五配位的畸变三角双锥构型和六配位的畸变八面体构型。配合物对人肝癌细胞(HUH7)、人肺癌细胞(A549)、人表皮癌细胞(A431)、人结肠癌细胞(HCT-116)和人乳腺癌细胞(MDA-MB-231)均有较强的抑制活性。 相似文献
222.
Functionalized 1-C-alkynyl sugars are prepared from 2-acetoxy-glucal triacetate. Dicobalt complexes of these sugar acetylenes can stabilize the anomeric carbenium cations, which promote the Ferrier-type rearrangement through the 5,6-dehydro precursors to afford alkynyl cyclohexanones after decomplexation. High stereoselectivity resulted from suitable steric interaction between the C-2 O-protecting group and the alkynyl substituents. Molecular mechanism is discussed. 相似文献
223.
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225.
A. M. Vasil'tsov E. Yu. Shmidt A. I. Mikhaleva A. V. Afonin A. B. Zaitsev 《Chemistry of Heterocyclic Compounds》2001,37(12):1488-1492
The oxime of 5-pregnen-3-ol-20-one reacts with acetylene in the KOH-DMSO system to form a mixture of products containing 3-vinyloxy-17-(1-vinyl-2-pyrrolyl)-5-androstene as the major product (63% yield) and also the O-vinyloxime of 3-vinyloxy-5-pregnen-20-one (10%), 3-vinyloxy-17- and 3-vinyloxy-17-5-pregnen-20-one (25%, 1:4 ratio). 相似文献
226.
János Halász Szilvia Mészáros István Hannus 《Reaction Kinetics and Catalysis Letters》2006,87(2):359-365
Summary Some of the chlorinated organic compounds are widely used commercially because of their advantageous chemical/physical properties
or being toxic to pestiferous living substances. We have prepared and applied monometallic Co-, Pt- and bimetallic Co,Pt-ZSM-5
zeolite catalysts for hydrotreating 2- and 4-chlorophenols in the temperature range of 300-400 oC using a fixed-bed laboratory
reactor system equipped with a gas chromatograph for analysis. In the reaction over the Pt-containing catalyst high initial
conversion can be observed, the compounds transform to cyclohexanone, however, the activity of the catalyst decreases even
during the 2 h reaction time. In the presence of Co-ZSM-5, the main reaction is simple hydrodechlorination resulting in phenol
as the main product, and this catalyst is stable, and the activity does not change. The bimetallic catalyst combines the advantages
(and disadvantages) of the monometallic samples. The hydroconversion of chlorophenols resulted in the formation of cyclohexanone
with high initial selectivity. However, because of the relatively short catalyst lifetime further optimization is necessary
before practical application.</o:p> 相似文献
227.
Pd-Ce-B/水滑石催化液相苯酚选择性加氢制环己酮 总被引:1,自引:0,他引:1
以Al3 /(Al3 Mg2 )摩尔比为0.2的水滑石(HT)为载体,采用还原浸渍法制备了负载型Pd-Ce-B/HT催化剂,并将其应用于液相苯酚选择性加氢制环己酮.与Pd-Ce-B/Al2O3,Pd-Ce-B/MgO和Pd-Ce-B/SiO2相比,Pd-Ce-B/HT催化剂具有高活性和高环己酮选择性.5.8%Pd-Ce-B/HT上苯酚的转化率和环己酮的选择性分别达82.0%和80.3%,显示了其潜在的工业化应用前景.根据多种表征结果,初步讨论了催化剂的构效关系以及添加剂Ce3 和载体酸碱性对催化性能的促进作用. 相似文献
228.
B. A. Trofimov O. A. Tarasova E. Yu. Shmidt A. I. Mikhaleva L. M. Sinegovskaya 《Russian Chemical Bulletin》1997,46(3):594-596
Transformation ofO-vinylacetophenone oxime in the system ButOK-THF was studied. The reaction at 60–65 °C was shown to afford not the anticipated 2-phenylpyrrole, but, instead, 2,4-diphenylpyrrole
(21% yield) and oligomer products (40% yield). The latter have the same elemental composition as the startingO-vinyl oxime but do not contain vinyloxy groups or pyrrole fragments.
Translated fromIzvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 615–617, March, 1997. 相似文献
229.
E. A. Dikusar N. A. Zhukovskaya K. L. Moiseichuk O. G. Vyglazov 《Chemistry of Natural Compounds》2007,43(4):369-373
The aldehyde jasmorange (1) was converted to the oxime (2), acylation of which by alkylcarboxylic acid anhydrides in the presence of HClO4 or by acid chlorides in the presence of pyridine synthesized esters of jasmorange oxime 3–24 in 82–91% yields. Refluxing 3–24 in hexane converted them quantitatively into nitrile 25.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 307–310, July–August, 2007. 相似文献
230.
Dmitri L. Chizhov Dmitri V. Sevenard Kazimir I. Pashkevich 《Journal of fluorine chemistry》2004,125(7):1137-1141
Several new mononuclear complexes of Pd(II) have been prepared from perfluorobutyl substituted 1,3,5-triketones (containing linear and carbocycle backbones) and perfluoroheptanoyl cyclohexanone. 1,3-Diketones formed a mixture of trans- and cis-forms, whereas 1,3,5-triketones gave trans-complexes exclusively. The enolization of the non-bonded carbonyls in this case depends on the nature of substituents at positions 2 and 4 of the 1,3,5-triketone moiety. The molecular structure of one triketonate complex was confirmed by X-ray single crystal investigation. 相似文献