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1.
二烃基锡双(O,O-二硫代磷酸酯)的合成和波谱研究   总被引:1,自引:0,他引:1  
合成了15个二烃基双(O,O-二硫代磷酸酯)化合物。利用IR、(1H、13C、119Sn)NMR表征了化合物的结构。这是一类六配位变形八面体结构的二烃基锡化合物。对化合物的质谱裂解机制进行了讨论。  相似文献   

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合成了 6种 O,O′,O′′,O′′′-四芳基双二硫代磷酰亚胺的合成类化合物 ,产物经元素分析、IR,1 H NMR和 MS表征。  相似文献   

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本文介绍O,O-二烷基氢膦酸酯中发生在σ^4λ^5P-H或σ^3λ^3P-OH键上的几类重要反应如烷基化反应、加成反应、Atherton-Todd反应等,以及这些反应在有机合成中的应用,并对某些新颖反应机理作初步探讨。  相似文献   

6.
在催化量氢氧化铯存在下,O,O-二烷基膦酸酯与二芳基二硒醚在DMSO中、室温、空气氛中反应,高收率得到磷酸硒酯.反应机理为氢氧化铯与O,O-二烷基膦酸酯反应生成的(RO)2P-(O)Cs+,(RO)2P-(O)Cs+亲核进攻ArSeSeAr生成磷酸硒酯和ArSe-Cs+,后者在水存在下,被氧化得到ArSeSeAr和氢氧化铯.这方法为合成磷酸硒酯提供了一条简便有效的路径.  相似文献   

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本文合成了13种三苯基锡-O,O-二芳基二硫代磷酸酯,测定了它们的IR、~1H、~(31)C、~(119)SnNMR,MS和元素分析,结果表明该类化合物具有单体的四面体四价锡结构。  相似文献   

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本文介绍O,O-二烷基氢膦酸酯中发生在σ ̄4λ ̄P─H或σ ̄3λ ̄3P─OH键上的几类重要反应如烷基化反应、加成反应、Atherton-Todd反应等,以及这些反应在有机合成中的应用,并对某些新颖反应机理作初步探讨。  相似文献   

10.
用TG-DTG-DSC热分析技术研究了三(O,O′-二异丙基二硫代磷酸酯)合钴(Ⅲ)、双(O,O′-二乙基二硫代磷酸酯)合镍(Ⅱ)及其后者与吡啶或4-甲基吡啶加合物在氮气气氛中的热行为;用传统的微商法(A-B-S)和积分法(C-R法)以及分别由Malek、Dollimore提出的两种新型的热分析动力学方法协同处理TG数据,获得了四种配合物的热分解反应动力学参数EA,确定了反应机理。对它们的热行为和分子结构之间的关系进行了讨论;并试就本文所用的几种数据处理方法作了比较。  相似文献   

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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%.  相似文献   

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Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields.  相似文献   

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In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments.  相似文献   

14.
The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula.  相似文献   

15.
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines.  相似文献   

16.
KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields.  相似文献   

17.
The review contains a concise historical account and information on the most significant researches undertaken by the staff at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry of Heterocyclic Compounds. Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008.  相似文献   

18.
A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL.  相似文献   

19.
Zhanhui Yang  Shiyi Yang  Jiaxi Xu 《Tetrahedron》2017,73(23):3240-3248
Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products.  相似文献   

20.
A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions.  相似文献   

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