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苝酰亚胺衍生物是国内外近年来广泛研究的π-共轭低聚物,由于其独特的半导体传导性、高热稳定性、较高的电子亲和性和卓越的传输性能在众多领域具有潜在的应用价值。通过对其海湾位置进行结构修饰,可进一步改善其物理化学性能。本文利用苝酰亚胺的Stille偶联反应合成了一种新型的聚(N,N’-二(2-乙基己基)苝-3,4,9,10-四甲酸二酰亚胺),它具有近似石墨烯带状的规整结构和宽广的光谱吸收,成功将苝核四溴代的海湾位置用四丁基锡取代,对产品分别进行了IR、NMR和GPC-MALLS表征,并对这种具有特殊π-共轭结构的新型聚合物的光化学性能进行了研究。 相似文献
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以含有不同取代基的吡啶为起始原料,α-氨基酸为手性源,设计并合成了新型的含有手性中心的联吡啶衍生物,其结构经1H NMR, 13C NMR和HR MS(ESI)表征。 相似文献
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镍络合物催化条件下2,2'-联吡啶的偶联合成 总被引:2,自引:2,他引:2
在制备联吡啶的偶联反应中,镍化合物和三苯基膦通常是以化学计量参与反应 。我们在对Tiecco报道的偶联反应进行研究的过程中发现,这一反应可以在催化条 件下进行。这一改进订基于投料顺序的改变,充分利用零价镍当场(in situ)生 成时的高活性。将氯化镍、三苯基膦、2-溴吡啶先溶于DMF中,然后在50 ℃时加入 锌粉,催化偶联生成联吡啶,可以获得满意的收率。同时对三种镍化合物的反应活 性作了比较,以NiCl_2·6H_2O活性最高。 相似文献
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首次以芳基三氮烯为新型亲电底物进行Stille偶联反应研究.反应在室温、氩气保护下进行.溶剂、两底物物质的量比、催化剂用量等影响收率的因素被优化,取得最佳的优化条件,获得较好的收率.芳基三氮烯通过助催化剂路易斯酸迁移到钯化合物,偶联反应由钯催化剂催化完成.产物纯化通过硅胶柱层析完成,结构被1H NMR,13C NMR确定. 相似文献
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以2种配体4,4′-dimethyl-2,2′-bipyridine(L1)和4′-methyl-(2,2′-bipyridine)-4-carbaldehyde oxime(L2),分别与芳基钌二聚体[RuCl_2(η~6-p-cymene)]2合成了2种新型单核配合物[Ru(η~6-p-cymene)(L1)Cl]Cl(1)和[Ru(η6-p-cymene)(L2)Cl]Cl(2)。应用元素分析、ESI-MS和~1H NMR对配合物的组成和结构进行表征,通过紫外光谱法和荧光光谱法研究了配合物的水解及其与CT-DNA和血清蛋白的结合性质,并且进行了细胞毒性研究。结果表明,在水溶液中配合物1比2在动力学上更稳定(k:0.383 h~(-1)(1)、1.458 h~(-1)(2));配合物均通过嵌入作用与双链DNA结合,但2有较强的结合能力(Kb:7.8×10~3L·mol~(-1)(1)、1.86×10~4L·mol~(-1)(2))。配合物均能与蛋白质发生相互作用,引起蛋白静态猝灭,但1作用较强(KA:1.04×10~5L·mol~(-1)(1)、8.62×10~4L·mol~(-1)(2))。配合物与蛋白的较强结合能力,可能是其细胞毒性不高的原因。 相似文献
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The Stille cross-coupling reactions of aryl halides with aryl or alkynylstannanes have been achieved under mild conditions in 1-butyl-3-methylimidazolium hexafluorophosphate ([bmim][PF6]), affording the corresponding biaryls and aromatic acetylenes in good yields. Use of this solvent allows for facile recycling of the solvent and catalyst system, which can be used at least five times without loss of activity. 相似文献
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K. C. Nicolaou Nicolas Winssinger Joaquin Pastor Fiona Murphy 《Angewandte Chemie (International ed. in English)》1998,37(18):2534-2537
No heteroatom required! In many solid-phase syntheses, after the release from the polymer support a heteroatom (e.g. O, S, N) remains in the substrate as a residue of a linking protecting group. With polymer-bound tin reagents cleavage and cyclization of the substrate with C–C bond formation (see picture) can now be achieved by intramolecular Stille coupling. S =substrate. 相似文献
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P. MalleshamB.V.D. Vijaykumar Dong-Soo Shin S. Chandrasekhar 《Tetrahedron letters》2011,52(46):6145-6147
Total synthesis of (−) Radicamine-B is achieved in eight steps from (R)-(+)-Garner aldehyde in a stereoflexible manner involving Stille coupling and one-pot domino epoxidation-pyrrolidine formation as key steps. 相似文献
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1,5-Disubstituted 3-trifluoromethylpyrazoles were reacted with N-bromosuccinimide in DMF at room temperature or 70-80 °C for 1-2 h to afford the corresponding 4-bromo-substituted pyrazoles 2 in 95-99% yields. The microwave-assisted Stille coupling reactions of 2 with arylstannanes having a substituent on the benzene ring and allylstannane in refluxing CH3CN in the presence of Pd(PPh3)4 provided the corresponding 1,4,5-trisubstituted 3-trifluoromethylpyrazoles 3 in 75-98% yields. 相似文献
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Thomas E. Nielsen 《Tetrahedron》2005,61(33):8013-8024
A study on the Stille reaction of alkenyl iodides and stannanes with structural resemblance to retrosynthetic fragments of a projected total synthesis of the marine alkaloid zoanthamine was carried out. A range of reaction conditions was examined, and a protocol developed by Corey utilizing excess copper(I) chloride and lithium chloride was found to be most efficient. The methodology was successfully applied to join two major fragments of the zoanthamine skeleton. 相似文献
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Adam F. Littke Gregory C. Fu 《Angewandte Chemie (International ed. in English)》1999,38(16):2411-2413
A “one-two punch” comprising two commercially available reagents, PtBu3 and CsF, provides a practical and general solution for a long-standing limitation of the Stille reaction—the inability to couple inexpensive and readily available aryl chlorides [Eq. (1); R1=OMe, NH2, o-Me, etc.; R=vinyl, allyl, Ph, Bu, etc.]. 相似文献
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Reyhan BastinJames W. Dale Michael G. EdwardsJulien P.N. Papillon Michael R. WebbRichard J.K. Taylor 《Tetrahedron》2011,67(51):10026-10044
A formal synthesis of neooxazolomycin is described via the preparation of Kende’s key intermediate in a longest linear sequence of 23 steps. This work is founded upon the union of three fragments: Moloney’s lactam-derived triflate, a vinyl stannane and a Julia-Kocienski sulfone and encompasses three key steps: (i) a Stille cross-coupling to combine the triflate and vinyl stannane, (ii) a base-promoted enone deconjugation to derive the dihydroxylation precursor and (iii) our previously reported Julia-Kocienski methodology to assemble the pentadienyl amine side chain with the sulfone precursor. 相似文献
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A series of aryl ferrocenyl ketones were prepared from iodoferrocene, phenylboronic acids, and CO via palladium‐catalyzed carbonylation coupling in a short time. The procedure was efficient and convenient and avoided formation of diacylated derivatives compared with currently available Friedel–Crafts acylation methodologies. 相似文献