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991.
Petr Novk Zdeka Padlkov Lenka Kolov Ivana Císaov Ale Rûi
ka Jaroslav Hole
ek 《应用有机金属化学》2005,19(10):1101-1108
Tri‐ and di‐organotin(IV) compounds containing one or two 2‐(dimethylaminomethyl)phenyl‐ (LCN) groups as chelating ligands were prepared by reactions of lithium compound LCNLi with an appropriate amount of (organo)tin halide. The geometry of tin in 1 ((LCN)2SnPhCl) is on the boundary between octahedral and trigonal bipyramidal. The diorganotin compounds 2–4 ((LCN)2SnX2, where X = Cl, Br, I) have a distorted octahedral geometry in the solid state and show dynamic processes in solution with a lowering of activation energy of the dynamic process going from diiodide to dichloride derivative. Compound 5 (LCNSnPhCl2) has a trigonal bipyramidal structure with non‐equivalent chlorine atoms. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
992.
993.
GE HanQing LENG Yan ZHANG FuMin PIAO JiaRui ZHOU ChangJiang & WANG Jun State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemistry Chemical Engineering Nanjing University of Technology Nanjing China Petrochemical Research Institute PetroChina Company Ltd. Beijing 《中国科学B辑(英文版)》2009,(8)
Pyridine(Py)-modified Keggin-type vanadium-substituted heteropoly acids(PynPMo10V2O40,n=1 to 5) were prepared by a precipitation method as organic/inorganic hybrid catalysts for direct hydroxylation of benzene to phenol in a pressured batch reactor and their structures were detected by FT-IR.Among various catalysts,Py3PMo10V2O40 exhibits the highest catalytic activity(yield of phenol,11.5%),without observing the formation of catechol,hydroquinone and benzoquinone in the reaction with 80 vol% aqueous acetic ... 相似文献
994.
995.
996.
In the presence of pyridine, the Pd-catalyzed addition reaction of CO and CCI4 to 1-octene could be carried out smoothly under mild conditions. In this reaction, the satisfactory results were afforded when different alcohols and palladium catalysts were used. 相似文献
997.
Hong‐Ji Jiang Hong‐Yu Wang Rui Zhu Jun‐Hua Wan Feng Liu Jia‐Chun Feng Wei Wei Wei Huang 《Journal of polymer science. Part A, Polymer chemistry》2008,46(5):1548-1558
To investigate the fine optoelectronic difference of the target oligomers with or without peripheral fluorene moieties, two dumbbell‐shaped oligomers ( F0 and F1 ) were designed and convergently prepared via Suzuki coupling reaction. The molecular structures of the oligomers were fully characterized by 1H NMR, 13C NMR, and MALDI‐TOF mass spectra, respectively. The absorption, photoluminescent behavior, and energy band gaps of the oligomers were examined through UV–vis, photoluminescent spectra and cyclic voltammetry. The experimental results demonstrate that the absorption and photoluminescent properties are little affected by molecular architecture, while the absolute photoluminescence quantum efficiency of films and energy band gaps derived from cyclic voltammetry in solution are strongly correlated with the molecular frameworks. The observed energy band gaps of oligomers are further validated by the different molecular orbital contours of the HOMO energy levels from theoretical calculations. Preliminary electroluminescent investigations for F1 have also been conducted and discussed. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1548–1558, 2008 相似文献
998.
An organotin(Ⅳ) complex [(CH3)2Sn(4-FC6H4CONHO)2] has been synthesized and characterized by elemental analysis, IR, 1H NMR and X-ray single-crystal diffraction techni-ques. The crystal belongs to the orthorhombic system, space group Pbca with a = 9.7565(13), b = 17.664(2), c = 20.784(3) A, Z= 8, V= 3581.9(8) A3 Dc = 1.695 g/cm3, μ(MoKα) = 1.469 mm-1, F(000) = 1808, R = 0.0321 and wR = 0.0838. In the molecular structure of the title complex, the tin atoms are five-coordinated in a trigonal bipyramidal geometry, and the special coordination properties of dimethyltin(Ⅳ) with hydroxamate-type ligands are also discussed. 相似文献
999.
Di-n-butyltin oxide reacted with p-[N,N-bis(2-chloroethyl)amino]benzoic acid to yield the compounds {{4-[(ClCH2CH2)2N]C6H4COOSnBu2}2O}2 (1) and {4-[(ClCH2CH2)2N]C6H4COO}2SnBu2 (2), which have been characterized by IR and ^1H NMR spectra. The X-ray diffractional studies of 1 reveal the structure of the molecule to be a dimer, in which the two Bu2Sn groups were linked via two bridging oxygen atoms to form a central Bu4Sn2O2 unit. And the tin atom adopts two carbons from two n-butyl groups and three oxygen atoms from the acid and the bridging oxygen. In vitro test showed compound 1 to exhibit high cytotoxicity against P388 and HL-60 cell lines. 相似文献
1000.
Nassarius reticulatus (whelk) imposex levels and organotin body burden (b.b.) were surveyed along the Portuguese coast, from Vila Praia de Âncora (northern limit) to Lagos (southern limit), between May and August 2003. The percentage of females affected with imposex (%I), the relative penis length index (RPLI), the vas deferens sequence index (VDSI) and the degree of female oviduct convolution index (AOS) were used to assess the level of imposex at each site. These imposex indices were determined for 23 sampling stations throughout the coast and were in the range 0.0–100%, 0.0–90%, 0.0–5.0 and 0.0–1.3 respectively. Sterile females (i.e. females carrying aborted egg capsules inside the capsule gland) were found inside the harbours of Viana do Castelo (8.5%) and Aveiro (3.7%). Organotin compounds were assessed at 10 sampling sites spread along the coast. Tributyltin (TBT) b.b. in females varied between 39 and 1679 ng g?1 (as tin) dry weight, and dibutyltin (DBT) and monobutyltin (MBT) varied in the ranges 23–1084 ng g?1 (as tin) d and 18–939 ng g?1 dry wt respectively. Among the butyltins, the major fraction corresponded to TBT (47.4%), followed by DBT (27.6%) and MBT (25.0%), which indicates recent TBT inputs. Triphenyltin (TPT) levels ranged from <5 to 21 ng g?1 (as tin), and, when quantifiable, represented on average 10% of that of TBT. TPT was the dominant phenyltin and was detected in 60% of the sampling stations. The imposex was significantly correlated to ln (TBT) (Spearman r = 0.918, p < 0.001 for RPLI; r = 0.864, p < 0.001 for VDSI; r = 0.828, p < 0.01 for AOS). The higher levels of imposex and TBT contamination occurred inside or close to harbours, which we identified as ‘hotspots’ of pollution along the coast. Comparing the results obtained in the current work with those reported in a similar survey in 2000, imposex and TBT b.b. varied locally but did not reveal any global trend in the variation of TBT pollution along the Portuguese coast over the 3 year period. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献