共查询到20条相似文献,搜索用时 78 毫秒
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甘氨酸—N,N—双亚甲基膦酸锆—钯催化剂的催化加氢性能 总被引:7,自引:3,他引:7
甘氨酸┐N,N┐双亚甲基膦酸锆┐钯催化剂的催化加氢性能傅相锴*马学兵刘昌华何佑秋(西南师范大学化学化工学院重庆630715)关键词甘氨酸-N,N-双亚甲基膦酸锆,钯催化剂,催化加氢,催化活性1996-03-25收稿,1996-06-19修回国家自然科... 相似文献
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新型负载配位催化剂ZBDPPEDAEPA/TiO2/Pd催化羰化反应研究 总被引:1,自引:0,他引:1
用乙二胺-N'-乙基膦酸的氨基与季盐[Ph2P+(CH2OH)2]Cl-,经曼尼希反应合成了N,N-双二苯膦甲基-乙二胺-N'-乙基膦酸(Ph2PCH2)2NCH2CH2N+H2CH2CH2PO3H-(BDPPEDAEPA), 并制备了相应的(N,N-双二苯膦甲基-乙二胺-N'-乙基膦酸-磷酸氢)锆载体Zr(HPO4)1.35[(Ph2PCH2)2NCH2CH2NHCH2CH2PO3]0.65·H2O (ZBDPPEDAEPA) 及二氧化钛和二氧化锆微粉表面包膜了ZBDPPEDAEPA的新型催化剂载体ZBDPPEDAEPA / TiO2、ZBDPPEDAEPA/ ZrO2和相应的钯催化剂ZBDPPEDAEPA / Pd、ZBDPPEDAEPA / TiO2 / Pd、ZBDPPEDAEPA/ZrO2/Pd. 在常压条件下, 对该类催化剂催化氯苄羰化反应的活性及产物组成作了初步考察. 对催化剂载体的粒径分析表明, ZBDPPEDAEPA / TiO2 / Pd的高活性归因于ZBDPPEDAEPA / TiO2载体的颗粒均匀、平均粒径小.ZBDPPEDAEPA以平均50 nm的薄层包膜在TiO2上, 这层包膜属于纳米级催化材料. 相似文献
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含膦,氮配体的混合膦酸锆—钯催化剂的研制 总被引:6,自引:3,他引:6
用氯化二苯基膦为膦化试剂,首次对多乙烯多胺乙基膦酸-磷酸氢锆Zr(HPO4)1.35(O2PCH2CH2(NHCH2CH2)mNH2)0.65·H2O(ZP-PEPAEPA,n=0,1,2,3,4)载体表面进行二苯基膦化,合成了一类含膦氮配体的新型混合膦酸锆载体及负载钯催化剂。研究了有机膦酸侧链不同链长和Ph2PCl用量对配体载体制备的影响,并用IR,TG,DTG,DTA对这类载体及催化剂进行表征 相似文献
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本文报道高分子膦-钯络合催化剂的合成及对催化剂催化加氢的活性、稳定性进行考察的结果。与文献对比表明,高分子膦-钯络合催化剂具有良好的稳定性和催化活性,膦化物不失为一类优良的配位体。 相似文献
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手性胺-质子酸是近年来发展起来的新型高效、高对映选择性的有机催化体系, 已成功应用于催化不对称Aldol反应、Michael加成反应、Diels-Alder反应和Strecker反应等许多重要的有机合成反应. 价廉易得的质子酸的引入不仅可促进活性中间体烯胺的生成, 并可通过形成的氢键稳定反应的过渡态, 从而显著提高该催化体系的催化活性和立体选择性. 对各类手性胺-质子酸催化剂在有机催化不对称合成反应中的应用、不对称诱导反应的机理、手性胺和质子酸的分子结构对其催化活性和不对称诱导活性的影响进行了评述. 相似文献
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Summary The phosphinic acid chlorides6 and9 react in good yields with N,N-dimethylaminoethanol to the corresponding esters3 and10. Reaction of the phenylphosphonous acid esters1 and2 with arylbromides, heteroarylbromides and carboxylic acid chlorides give esters of unsymmetrical phosphinic acids. Similarly, cyanphenylphosphinic acid ethylester reacts with aliphatic amines to phosphonic acid esterchlorides. 相似文献
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Bao-qing Shentu Ji-peng Li Zhi-xue Weng 《高分子科学》2006,(4):345-351
The effect of N,N,N',N'-tetraalkyl terephthalamide (TATA) on the non-isothermal crystallization and melting characteristics ofpolypropylene (PP) was studied. The addition of TATA can lead to the formation ofβ-crystal PP. With the increase in TATA concentration the degree of crystallinity for β-crystal PP increased significantly, and that for a-crystal PP decreased, which indicated that TATA effectively induced the formation of β-crystal PP. WAXD also revealed the existence of β-crystal PP after the introduction of TATA into PP. PP containing TATA crystallized at a temperature range of 5-10℃ higher than that of pure PP, and the half-crystallization time (t1/2) and Avrami exponent (n) of PP at the same cooling rate were decreased by the addition of TATA, indicating that TATA influenced the crystallization rate and crystallization growth mode of PP. The rate constant of crystallization of PP containing TATA (Zc) was larger than that of pure PP, which further indicated that the crystallization of PP was accelerated by the addition of TATA. 相似文献
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研究新型萃取剂从硝酸盐介质中萃取分离稀土元素对于后处理工艺具有重要意义。本文报道以甲苯为稀释剂,N,N,N′,N′-四丁基丙二酰胺(TBMA)从硝酸盐介质中萃取铈(Ⅲ)、镝(Ⅲ)、铒(Ⅲ)、镨(Ⅲ)、钐(Ⅲ)、铽(Ⅲ)、铥(Ⅲ)、镱(Ⅲ)的机理。考察了硝酸浓度、TBMA浓度、盐析剂浓度以及温度对上述三价镧系离子分配比的影响。得出萃合物的组成主要是三配体配合物M(NO3)3·3TBMA;计算出萃取反应的条件平衡常数、萃取平衡常数。温度效应研究表明萃取反应主要是焓驱动的。对萃取分离系数以及TBMA萃取三价镧系离子的规律进行了初步研究。 相似文献
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Screening of N,N‐bidentate and N,N,N‐tridentate pyridine‐based ligands in the catalytic allylic oxidation of cyclic olefins
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A variety of chiral N,N‐bidentate and N,N,N‐tridentate ligands based on the pyridine framework, namely C2‐symmetric dipyridylmethane and terpyridine, N‐(p‐toluensulfinyl)iminopyridines and two kinds of iminopyridines, has been assessed in the asymmetric copper(I)‐catalysed allylic oxidation of cyclic olefins. Catalytic activity and enantioselectivity were found to be highly dependent upon the framework of the ligands, which afforded cycloalkenyl benzoates in low to moderate yields and enantioselectivities. The best yields (up to 70%) and enantioselectivities (up to 53% enantiomeric excess) were obtained with an iminopyridine based on camphane and quinoline skeletons. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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新的核苷衍生物N2,N3-亚乙烯基腺嘌呤核苷的合成 总被引:4,自引:0,他引:4
描述了一条有效的合成新的荧光核苷衍生物N2,N3-亚乙烯基腺苷的合成路线.实验中首先通过6步制备了N2,N3-亚乙烯基鸟苷,然后经过氯化,再氨化得到标题化合物.标题化合物和新的中间化合物的结构分别通过1H NMR, MS和HRMS进行了确证,标题化合物的荧光性质初步得到证实. 相似文献
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Arpan Mukherjee Tuhin Subhra Koley Ayan Chakraborty Dr. Kallol Purkait Dr. Arindam Mukherjee 《化学:亚洲杂志》2021,16(22):3729-3742
Half-sandwich RuII complexes, [(YZ)RuII(η6-arene)(X)]+, (YZ=chelating bidentate ligand, X=halide), with N,N and N,O coordination ( 1 – 9 ) show significant antiproliferative activity against the metastatic triple-negative breast carcinoma (MDA-MB-231). 3-aminobenzoic acid or its methyl ester is used in all the ligands while varying the aldehyde for N,N and N,O coordination. In the N,N coordinated complex the coordinated halide(X) is varied for enhancing stability in solution (X=Cl, I). Rapid aquation and halide exchange of the pyridine analogues, 2 and 3 , in solution are a major bane towards their antiproliferative activity. Presence of free −COOH group ( 1 and 4) make complexes hydrophilic and reduces toxicity. The imidazolyl 3-aminobenzoate based N,N coordinated 5 and 6 display better solution stability and efficient antiproliferative activity (IC50 ca. 2.3–2.5 μM) compared to the pyridine based 2 and 3 (IC50>100 μM) or the N,O coordinated complexes ( 7 – 9 ) (IC50 ca. 7–10 μM). The iodido coordinated, 6 , is resistant towards aquation and halide exchange. The N,O coordinated 7 – 9 underwent instantaneous aquation at pH 7.4 generating monoaquated complexes stable for at least 6 h. Complexes 5 and 6 , bind to 9-ethylguanine (9-EtG) showing propensity to interact with DNA bases. The complexes may kill via apoptosis as displayed from the study of 8 . The change in coordination mode and the aldehyde affected the solution stability, antiproliferative activity and mechanistic pathways. The N,N coordinated ( 5 and 6 ) exhibit arrest in the G2/M phase while the N,O coordinated 8 showed arrest in the G0/G1 phase. 相似文献