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951.
Qingli Hao Hoong‐Kun Fun Suchada Chantrapromma Ibrahim Abdul Razak Fangfang Jian Xujie Yang Lude Lu Xin Wang 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(6):717-718
The title coordination complex, [Ni(C14H14O2PS2)2(C12H8N2)] or [Ni(pMePh‐dtp)2(phen)] (phen is 1,10‐phenanthroline; dtp is diaryldithiophosphate), has a non‐crystallographic twofold axis of symmetry through the Ni atom and the phen moiety. Two O,O‐di‐p‐tolyldithiophosphate (dtp) ions act as bidentate ligands. The central metal atom is coordinated by four S atoms from two dtp groups and two N atoms from the phen ligand. The title compound displays distorted octahedral geometry around the central Ni atom. 相似文献
952.
Yong Nie Chun‐Hua Hu Xue Li Wei Yong Jian‐Min Dou Jie Sun Ruo‐Shui Jin Pei‐Ju Zheng 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(8):897-899
Each of the title compounds, 8‐methoxy‐7,7‐bis(triphenylphosphine‐P)‐8,9:10,11‐di‐μH‐7‐platina‐nido‐undecaborane dichloromethane hemisolvate, [Pt(CH14B10O)(C18H15P)2]·0.5CH2Cl2, (I), 8‐isopropoxy‐7,7‐bis(triphenylphosphine‐P)‐8,9:10,11‐di‐μH‐7‐platina‐nido‐undecaborane dichloromethane solvate, [Pt(C3H18B10O)(C18H15P)2]·CH2Cl2, (II), and 9‐isopropoxy‐7,7‐bis(triphenylphosphine‐P)‐8,9:10,11‐di‐μH‐7‐platina‐nido‐undecaborane dichloromethane solvate, [Pt(C3H18B10O)(C18H15P)2]·CH2Cl2, (III), has an 11‐vertex nido polyhedral skeleton, with the 7‐platinum centre ligating to two exo‐polyhedral PPh3 groups and an alkoxy‐substituted polyhedral borane ligand. Compounds (II) and (III) are isomers. The Pt—B distances are in the range 2.214 (7)–2.303 (7) Å for (I), 2.178 (16)–2.326 (16) Å for (II) and 2.205 (6)–2.327 (6) Å for (III). 相似文献
953.
The reaction of CuCl2 · 2 H2O, 1,10‐phenanthroline (phen), suberic acid and Na2CO3 in a CH3CN–H2O solution yielded blue needle‐like crystals of [Cu2(phen)2(C8H12O4)2] · 3 H2O. The crystal structure (monoclinic, P21/n, a = 10.756(2) Å, b = 9.790(2) Å, c = 18.593(4) Å, β = 91.15(3)°, Z = 2, R = 0.043, wR2 = 0.1238) consists of suberato‐bridged [Cu2(phen)2(C8H12O4)4/2] layers and hydrogen bonded H2O molecules. The Cu atoms are coordinated by two N atoms from one bidentate chelating phen ligand and three carboxyl O atoms from different suberato ligands to form distorted [CuN2O3] square‐pyramids with one carboxyl O atom at the apical position (d(Cu–N) = 2.017(2), 2.043(3) Å, basal d(Cu–O) = 1.936(2), 1.951(2) Å and axial d(Cu–O) = 2.389(2) Å). Two [CuN2O3] square‐pyramids are condensed via a common O–O edge to a centrosymmetric [Cu2N4O4] dimer with the Cu…Cu distance of 3.406(1) Å indicating no interaction between Cu atoms. The resultant [Cu2N4O4] dimers are interlinked by the tridentate suberato ligands to form [Cu2(phen)2(C8H12O4)4/2] layers parallel to (101). These are assembled via π‐π stacking interactions into 3D network with H2O molecules in the tunnels extending in the [010] direction. 相似文献
954.
CaCO3/polystyrene inorganic/organic composite nanoparticles (50 nm) with a core/shell structure were synthesized in 80% yield by emulsion polymerization. Nanometer CaCO3 was pretreated with γ‐methacryloxypropyltrimethoxysilane in order to introduce polymerizable groups onto its surface. Soxhlet extraction experiments have shown that only 4% of total encapsulating polystyrene (PS) was removable when the ratio of CaCO3 to styrene was relatively low (14.8–29.6%), indicating strong adhesion between CaCO3 and PS. 相似文献
955.
A novel hyperbranched conjugated chemosensor with bipyridyl groups as periphery groups(BPY-HPV) was synthesized.BPY-HPV was highly sensitive to metal ions(Cu2+,Ni2+) for the strong coordination interaction(Ksv at the order of 107 mol-1 L) monitored by fluorescence spectroscopy.Moreover,by hydrogen bonds and charge transfer interaction,BPY-HPV shows strong interaction with 1,1,2,2-tetrachloroethane whatever in CH2Cl2(Ksv~106 mol-1 L) or film. 相似文献
956.
Jie Ju Yu Jin Li Jian Rong Gao Jian Hong Jia Liang Han Wei Jian Sheng Yi Xia Jia 《中国化学快报》2011,22(4):382-384
An aqueous solution of hydrogen peroxide and hydrogen bromide illuminated by a 60 W incandescent light bulb serves as a source of bromine radicals.Various substituted toluenes(NO2,Cl,Br,H,CH3) were high selectively brominated at the benzyl position for monobromination in CH2C12 at ice water with catalyst free.This simple but effective bromination of toluene derivatives with an aqueous H2O2-HBr system is characterized with the use of inexpensive reagents and a lower impact on the environment, which make it a good alternative to the existing bromination methods. 相似文献
957.
958.
Atropoenantioselective Redox‐Neutral Amination of Biaryl Compounds through Borrowing Hydrogen and Dynamic Kinetic Resolution 下载免费PDF全文
Dr. Jianwei Zhang Prof. Dr. Jian Wang 《Angewandte Chemie (International ed. in English)》2018,57(2):465-469
We report herein a novel atropoenantioselective redox‐neutral amination of biaryl compounds triggered by a cascade of borrowing hydrogen and dynamic kinetic resolution under the cooperative catalysis of a chiral iridium complex and an achiral Brønsted acid. This protocol features broad substrate scope and good functional‐group tolerance, and allows the rapid assembly of axially chiral biaryl compounds in good to high yields and with high to excellent enantioselectivity. 相似文献
959.
Xiqiang Zhao Jian ZhangZhanlong Song Hongzhen LiuLongzhi Li Chunyuan Ma 《Journal of Analytical and Applied Pyrolysis》2011,92(1):43-49
The compressed wheat and corn straw bale were pyrolyzed on a microwave heating device self-designed and built with respect to the time-resolved temperature distribution, mass loss and product properties. Considering scale up and technology promotion of microwave pyrolysis (MWP), the investigations on electricity consumption and energy balance of MWP were carried out emphatically. The results indicated that MWP had obvious advantages over conventional pyrolysis, such as heating rapid and more valuable products obtained. The distribution of pyrolysis products such as gas, liquid and char was close to 1:1:1 due to the medium pyrolysis temperature and the slow heating rate, which was not favorable for the formation of gas and/or liquid products. The content of H2 attained the highest value of 35 vol.% and syngas (H2 and CO) was greater than 50 vol.%. The electricity consumption of MWP was between 0.58 and 0.65 kW h (kg straw)−1 and with the increase of microwave power, the electricity consumption required for pyrolysis of unit mass of straw increased. The minimum microwave power for MWP was about 0.371 kW (kg straw)−1 and the proportion of heat loss and conversion loss of electricity to microwave energy occupied in the total input energy was 42%. Data and information obtained are useful for the design and operation of pyrolysis of large-sized biomass via microwave heating technology. 相似文献
960.
Xiaoxi Li Haiyan Wu Jian Dai Ting Huang Yong Wang 《Journal of Polymer Science.Polymer Physics》2011,49(12):898-906
Previous work showed that there was a synergistic effect of nucleating agent (NA) and elastomer in improving the fracture resistance of isotactic polypropylene (PP), relating to the formation of large amounts of β‐PP (β‐NA nucleated system) or the decrease of the spherulites diameters of α‐PP (α‐NA nucleated system). To find the direct relation between the synergistic efficiency of NA/elastomer and the microstructures of the materials, in this work, the ethylene‐propylene‐diene terpolymer (EPDM) modified PP blends with compounded NAs (β/α) were adopted and the changes of the microstructure and mechanical properties were investigated comparatively. The results showed that, with the adjustment of the mass fraction of compounded NAs, the microstructures of PP matrix including supermolecular structure and the relative fraction of β‐PP (Kβ) change accordingly. Specifically, the Kβ of β‐PP was successfully adjusted in the wide range of 0–78.9%. Consequently, the stiffness and the fracture resistance of the PP/EPDM blends were easily controlled in different degrees. It is believed that this work could provide a guide map for the design and preparation of certain polymer blends satisfying certain requirement. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献