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1.
丁华胜  谢毓元 《化学研究》2005,16(2):109-112
N-酰基吡唑类化合物作为酰化试剂逐步引起了广泛关注,对其制备以及在醇解,氨解,格氏反应,瑞福尔马斯基反应等方面的用途做了探讨.  相似文献   

2.
氢基钨配合物;烷氧基钨配合物的合成及β-H消去反应  相似文献   

3.
烯胺酮的合成及其在有机合成中的应用   总被引:1,自引:0,他引:1  
李明  郭维斯  文丽荣  杨华铮 《有机化学》2006,26(9):1192-1207
烯胺酮是目前应用较为广泛的有机合成中间体, 对其合成及其作为中间体在有机化合物特别是杂环化合物的合成中的应用进行了综述.  相似文献   

4.
陈婷  谭效松 《化学通报》2012,(2):114-120
酰基膦酸酯是一类活泼的有机合成中间体。本文归纳介绍了此类化合物的合成方法以及其近年来在有机合成中的应用。  相似文献   

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手性亚砜的合成及其在不对称合成中的应用   总被引:1,自引:0,他引:1  
本文综述了手性亚砜的合成。由于亚砜结构上的特征以及与金属离子的络合能力,使手性亚砜在不对称合成中具有强烈的诱导作用,使它成为进行不对称合成的一个手段。本文列举了它在不对称合成中的应用情况。  相似文献   

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张友楚  吴露玲  黄宪 《合成化学》2003,11(2):99-105
综述了近年来烯碲化合物的合成及其在立体选择合成中的应用。参考文献49篇。  相似文献   

11.
We wish to report an approach (equation 1) to hydrophenanthrenes which shows considerable promise of providing a general synthetic route for diterpenes, steroids, triterpenes, and tetraterpenes. Herein we illustrate the utility of this Friedel-Crafts type of procedure3,6 by describing a synthesis of ferruginol (6) 7 and xanthoperol (8).8  相似文献   

12.
For the application of zeolites as heterogeneous catalysts, low diffusion resistance for hydrocarbons within the micropore is essential for improving product selectivity and catalyst lifetime. This problem has been overcome by reducing the crystal size. This review introduces size-controlled preparation of nano-sized zeolites via hydrothermal synthesis in water/surfactant/organic solvent (emulsion method) and their application to heterogeneous catalysts. The ionicity of the hydrophilic group in surfactant molecules and the concentration of the Si source affected the crystallinity and morphology of zeolites prepared using the emulsion method. When using a non-ionic surfactant, mono-dispersed silicalite-1 nanocrystals ~60?nm in diameter were successfully prepared. Nano- and macro-ZSM-5 zeolites with crystal sizes of ~150?C200?nm and 1.5???m, respectively, were prepared and applied to n-hexane cracking and acetone-to-olefin reactions to investigate the effect of zeolite crystal size on catalytic stability and light olefin yield. Application of nano-zeolite to light olefin production was effective in achieving faster mass transfer of hydrocarbon molecules within the micropore, which led to improvements in olefin yields and catalyst lifetime.  相似文献   

13.
The reaction of N 1-substituted-5-amino-4-cyanopyrazoles with malononitrile and diethylmalonate occurs with formation of 6-substituted pyrazolo[3,4-d]pyrimidines, and pyrazolo[3,4-b]pyridines respectively. The structures of the products and conceivable mechanisms are discussed.  相似文献   

14.
单斜BiV04的离子液体辅助水热合成及表征   总被引:1,自引:0,他引:1  
在离子液体[BMIM]Br辅助的水热条件下,合成了斜钒铋矿(Clinobisvanite,m-BiVO4)片状多面体微米晶.采用XRD,XPS,IR和SEM等对产物物相、结构和形貌进行了表征.结果表明,m-BiVO4产物为单斜晶系,I2/b空间群,片状多面体长宽为8~12 m,厚度为2-5 μm,晶型较完整,且具有良好...  相似文献   

15.
介孔分子筛V-MCM-41的水热法制备与合成机理   总被引:4,自引:0,他引:4  
 以十六烷基三甲基溴化铵为模板剂,廉价的工业级高模数比(3.3)的硅酸钠为硅源,通过水热法合成了V-MCM-41介孔分子筛. 考察了合成条件对产物织构的影响,并采用低温氮吸附法分析探讨了介孔分子筛V-MCM-41的合成机理. 结果表明,模板剂用量、 pH值、加料方式、晶化温度、晶化时间、陈化时间和焙烧气氛等合成条件对介孔分子筛的制备均有影响,其中晶化温度、 pH值和模板剂用量的影响最为明显. X射线衍射谱表明合成的介孔分子筛具有六方晶体结构. 红外光谱和紫外可见光谱表明V进入了介孔分子筛的骨架结构.  相似文献   

16.
白刺新碱是从中国沙漠植物白刺叶子中分离出来的生物碱.因为其特异的结构,引发了化学合成与生源关系方面的探讨.根据它与育亨宾结构的类似性,提出它可能来源于育亨宾.另一个可能则是来源于赖氨酸.以来源于赖氨酸的C(5)结构为原料的三步仿生合成取得了成功.对白刺新碱的化学合成、生源关系和仿生合成进展进行综述,以促进相关研究的进展.  相似文献   

17.
韩光范  王进军 《合成化学》1999,7(2):210-212
通过异色满酮-4的克莱森缩合反应得到其α,β-不饱和衍生物,后者分别与3,5-二氨基-4-苯偶氮吡唑,3-氨基-1,2,4-三唑和2-氨基-苯并咪唑缩合,得到相应的四环和五环系列标题物。所合成的新化合物的结构均经元素分析,IR及^1H NMR确证。  相似文献   

18.
The reaction of dihalohydrazones with Hünig's base gives 1-carbethoxy-3-phenyl-4-haloazodienes in-situ, which were found to combine with a variety of electron rich olefins to yield halo-substituted tetrahydropyridazines (Scheme 2 and Table 1 ). These haloazodiene cyclizations are best characterized as inverse electron demand, 4 + 2 hetero Diels-Alder reactions that maintain a high degree of regio- and stereochemical control (Schemes 5 and 6). The chloro-substituted tetrahydropyridazines that are formed give high yields of substituted pyridazines upon treatment with base (Table 1). The sequence of a chloroazodiene cyclization to a tetrahydropyridazine followed by an aromatization constitutes a new and general synthesis of substituted pyridazines. In contrast to the haloazodiene cyclizations, the novel cyclization reactions of the in-situ generated 1-carbethoxy-3-phenyl-4,4-dichloroazodiene were found to give N-aminopyrroles and pyridazines when combined with acyclic enamines (Table 3 ). However, reactions with cyclic enamines gave the N-aminopyrroles, pyridazines, a dihydropyridazine as products as well as the noncyclized enamine intermediates (Table 4 ). The noncyclized enamines could be converted to the N-aminopyrroles simply upon heating to higher temperatures, indicating a stepwise mechanism (Schemes 8 and 9). The examples described here are the first reported cyclization reactions for dichloroazodienes.  相似文献   

19.
A 1,2-metallate rearrangment of a higher order cuprate derived from an alpha-lithiated xylal derivative and tridecyllithium is the key step in a synthesis of D-erythro-sphingosine and ceramide. A convenient method for preparing alpha-lithiated glycals from alpha-phenylsulfinyl glycals is also described.  相似文献   

20.
胡世荣 《化学通报》2006,69(11):861-864
合成了两种新的光致变色化合物1-羟基-4-苯氧基-9,10-蒽醌及1-羟基-4-对氯苯氧基-9,10-蒽醌,并通过核磁共振谱、红外光谱、质谱和元素分析确定了其结构。通过紫外-可见光谱表征了其光致变色性,并讨论了结构对光致变色性的影响。  相似文献   

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