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1.
研究了2-氧代-2-氯-4-取代苯基-5,5-二甲基-1,3,2-二氧磷杂环己烷与3-羟基异唑的反应,得到的氧磷酰化产物含有顺反两种异构体,用1HNMR、31PNMR、X射线衍射确定了它们的构型,并讨论了亲核取代反应中手性磷原子构型保持和翻转的机理,测定了异构体的生物活性。  相似文献   

2.
合成了一系列新型O-糖基-甲氧甲酰基膦酰胺酯,并对O-糖基亚磷酰胺酯与氯甲酸甲酯的Arbuzov反应及其它有关反应进行了讨论。产物的结构经1HNMR、31PNMR、IR及元素分析确定。初步的生物活性测定结果表明,化合物3e对人肝癌Bel-7402细胞和人白血病HL-60细胞有一定的抑制作用。化合物3a对烟草花叶病毒有一定的抑制活性。  相似文献   

3.
用付里叶变换红外光谱及31PNMR,探索了2-乙酰基-5-甲基-1,2,3-二氮磷杂环戊二烯同丙炔醇的动态反应过程,推测了可能的反应机理,并通过对二配位磷化物对应的三配位磷化物(2-乙酰基-3-氯-5-甲基-1,2,3-二氮磷杂环戊烯)同丙炔醇反应的研究,验证了二配位磷化物反应机理的可能性。  相似文献   

4.
合成了4个含四氮杂大环配体和O,O'-二烃基二硫代磷酸根的镍配合物[Ni(hmtade){SSP(OR)2}2](hmtade=5,7,7,12,14,14-六甲基-1,4,8,11-四氮杂环十四-4,11-二烯;R=C6H5,2-naphthyl,C6H5CH2CH2,cyclohexyl),用元素分析、摩尔电导、红外光谱和1H NMR、31PNMR、电子光谱及差热分析对其结构进行了表征.研究结果表明:配合物均为非电解质,O,O'-二烃基二硫代磷酸根作为单齿配体对镍中心配位.对四氮杂大环的构型进行了讨沦.  相似文献   

5.
本文研究了苯基硫脲、苯基二氯化膦与脂肪醛(酮)在无水苯中进行的类Mannich反应,在分离产物时发现,除了生成3,4-二苯基-4-氧代-1,3,4-二氮磷杂环戊-2-硫酮(Ⅰ)外,还得到了少量3,4-二苯基-4硫代-1,3,4-二氮磷杂环戊-2-硫酮(Ⅱ).根据化合物Ⅱ的生成及31PNMR跟踪反应的结果,得出反应机理为P-H键对亚胺衍生物的加成.通过X射线衍射分析发现,化合物Ⅰ和Ⅱ的五元杂环均为平面结构,其平面性受4位氧代或硫代的影响较大.  相似文献   

6.
研究了氯代膦酰基异氰酸酯与5-氨基-3-苄硫基-1,2,4-三唑及其类似物的成环反应,合成了12个7-芳基(烷氧基)-2苄硫基-5,7-二氧代-4,5,6,7-四氢-7-磷杂-1,2,4-三唑[1,5a]三嗪,利用1HNMR、31PNMR确定其Z型,生物活性测定结果表明,部分化合物具有一定的除草活性。  相似文献   

7.
通过硫代磷酰-氯酯与N,N-二丙基-α-乙氨基乙酰胺反应合成了21种-α-硫代磷酰基胺基乙酰胺衍生物.所合成的化合物用元素分析、1H NMR和31PNMR进行了表征,并进行了杀虫和杀螨活性的试验.  相似文献   

8.
1978年Kem等曾报导,在三苯膦存在下,用双-环辛二烯镍和叶立德苯甲酰基亚甲基三苯膦反应,可得到化合物(Ⅰ): 仿此,我们合成了三种类似的新的氧、磷(砷)镍鳌合物,皆作了IR, 31PNMR和元素分析。  相似文献   

9.
通过相转移催化关环反应合成了新的6-取代-2-疏-2-烷(芳)氧-4-(2,-4二氯苯基)-4-氢-1,3,2-苯并二氧磷杂环已烷(3a-3g),用结晶法分离得到7对非对联消旋体,其结构经1HNMR、31PNMR和元素分析确证,化合物3a-A单晶X射线分析表明其构型为(2R,4S;2S,4R).生物活性测定结果表明,化合物3C有良好的杀虫活性,非对映消旋体A和B具有协同杀虫作用.  相似文献   

10.
在中压汞灯光照下,无机磷酸盐能促进尿嘧啶水溶液(pH=8)的光解作用(磷酸盐效应),发生嘧啶碱基的光解取代反应,主要光解产物为6-磷酸基尿嘧啶(C4H5N2O6P).通过元素分析,UV,IR,EIMS,1HNMR,13CNMR,31PNMR等测试手段和方法,确定了光解产物的组成和结构.实验表明,在中压汞灯的发射光谱(连续光谱)中,对磷酸盐效应起作用的波长为190~220nm.  相似文献   

11.
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   

12.
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   

13.
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives.  相似文献   

14.
The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion.  相似文献   

15.
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   

16.
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   

17.
N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%).  相似文献   

18.
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones.  相似文献   

19.
In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates.  相似文献   

20.
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   

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