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氮磷杂环丙烯络合物合成1,2-氮磷杂茂络合物反应机理的理论研究
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作者 王超 母伟花 方德彩 《化学学报》 SCIE CAS CSCD 北大核心 2006年第16期1665-1672,共8页
用密度泛函方法在B3LYP/6-31G*(除W原子采用LanL2DZ基组以外)水平上研究了氮磷杂环丙烯络合物(2H-azaphosphirenecomplex)热解生成1,3-偶极体腈磷叶立德络合物(nitriliumphosphanylidecomplex)以及腈磷叶立德络合物(nitriliumphosphanyl... 用密度泛函方法在B3LYP/6-31G*(除W原子采用LanL2DZ基组以外)水平上研究了氮磷杂环丙烯络合物(2H-azaphosphirenecomplex)热解生成1,3-偶极体腈磷叶立德络合物(nitriliumphosphanylidecomplex)以及腈磷叶立德络合物(nitriliumphosphanylidecomplex)与炔(alkyne)反应生成1,2-氮磷杂茂络合物.结果表明,第一步反应,即开环反应生成亚磷烯络合物,为反应的决速步骤,其位垒为84.3kJ?mol-1,然后生成的亚磷烯络合物与氰发生终端[1,1]加成反应生成腈磷叶立德络合物,最后该腈磷叶立德络合物与炔发生[3+2]加成反应,越过很低的位垒即可生成热力学稳定产物1,2-氮磷杂茂络合物.此外,还研究了不同取代基和催化剂五羰基合钨对反应机理及反应位垒的影响. 展开更多
关键词 杂环丙络合物 亚磷烯 叶立德 环加成 密度泛函
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Highly efficient Rh(Ⅰ)/tris-H_8-binaphthyl monophosphite catalysts for hydroformylation of dicyclopentadiene to dialdehydes 被引量:4
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作者 Mi Tian Haifeng Li Lailai Wang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第10期1646-1652,共7页
Novel catalytic systems for the Rh‐catalyzed hydroformylation of dicyclopentadiene have been developed using tris‐H8‐binaphthyl monophosphite as ligands containing different ester substituents at the 2’‐binaphthy... Novel catalytic systems for the Rh‐catalyzed hydroformylation of dicyclopentadiene have been developed using tris‐H8‐binaphthyl monophosphite as ligands containing different ester substituents at the 2’‐binaphthyl position(OCOMe,OCOPh,OCOAdamantyl and OCOPhCl).The catalysts exhibited high activity(S/C=4000,TON=3286)with good to excellent selectivity towards dialdehydes.Remarkably,the Rh(I)complex bearing the ligands with chlorophenyl ester substituents led to 99.9%conversion and 98.7%selectivity for dialdehydes under relatively mild conditions(6 MPa,120°C). 展开更多
关键词 HYDROFORMYLATION DICYCLOPENTADIENE Monophosphite DIALDEHYDE Homogeneous catalysis
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Effect of phosphite and epoxy soybean oil on heat stability of poly (vinylchloride) composite stabilizers 被引量:3
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作者 JIANG Ping-ping ZHANG Xiao-yan +1 位作者 DUAN Ru-zhe ZHANG Xiao-ming 《Journal of Chemistry and Chemical Engineering》 2007年第1期45-49,共5页
The influences ofphosphite and epoxy soybean oil in combination with liquid calcium/zinc isocaprylates on the thermal stability of flexible poly (vinyl chloride) were studied. The stabilizing effect of poly (vinyl ... The influences ofphosphite and epoxy soybean oil in combination with liquid calcium/zinc isocaprylates on the thermal stability of flexible poly (vinyl chloride) were studied. The stabilizing effect of poly (vinyl chloride) was evaluated by Congo red method, thermoaging test and Thermogravimetric-differential Scanning Calorimetry (TG-DSC). The results showed that the addition of the phosphite or epoxy soybean oil improved the thermal stability of PVC with the calcium/zinc isocaprylates stabilizing system, especially epoxidied soybean oil exhibited a remarkable effect, and the synergism on PVC thermal stability for 3:2 phenyl dioctyl phosphite to epoxidized soybean oil weight ratio was acquired. Accordingly, the rapid mass loss in TG curve occured between 258.9 ℃ and 334.4 ℃, which corresponded to the enthalpy of the pyrogenation of 609.2 J/g. It was also found that the stabilized PVC of the best ratio gave better mechanical and processing properties. 展开更多
关键词 thermal stability poly (vinyl chloride) Ca/Znstabilizers
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Interface and Surface Properties of Nano-hydroxyapatite /Poly (1,4-PhenyleneSulfide)-Poly(2,4-Phenylene Sulfide Acid) Copolymer Composite
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作者 严永刚 LI Yubao +3 位作者 Wei Jie Zuo Yi J.G.C.Wolke J.A.Jansen 《High Technology Letters》 EI CAS 2003年第1期26-30,共5页
The interface and surface properties of nano-hydroxyapatite(n-HA) and poly( 1, 4-phenylene sulfide)-poly (2,4-phenylene sulfide acid)(PPS-PPSA) copolymer composite were investigated. The results show that there are so... The interface and surface properties of nano-hydroxyapatite(n-HA) and poly( 1, 4-phenylene sulfide)-poly (2,4-phenylene sulfide acid)(PPS-PPSA) copolymer composite were investigated. The results show that there are some strong interface combinations of calcium ion (Ca2+ ), car-boxyl (-COO- ) and phosphate radicle ion (PO_4~3- ) between copolymer and n-HA in the composite. The presence of the 2,4-phenylene sulfide acid in copolymer can increase the affinity to n-HA, which causes the formation of chemical bindings between the PPS-PPSA copolymer and n-HA. XRD analysis and IR surface analysis indicate that n-HA is not encapsulated by copolymer but exposed on the surface of the composite, and has same structure and properties with the origi-nal n-HA. The presence of the interface chemical bindings between the PPS-PPSA copolymer and n-HA can increase the content of n-HA in composite but does not cause the decrease of the composite mechanical strength. 展开更多
关键词 PPS-PPSA copolymer nanohydroxyapatite composite interface and surface biomaterials
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