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1.
在氯化氢无水乙醇溶液存在下,利用芳胺盐酸盐法或醛胺缩合法,4H-[1]-苯并吡喃-4-酮可直接与甲醛和芳香胺发生Mannich反应,得到3-芳氨基甲基-4H-[1]-苯并吡喃-4-酮(3)。共合成了5个未见文献报道的新化合物,产量适中。用IR,MS,1HNMR和元素分析确定了产物(3)的结构,并对(3)的生成机理进行了讨论。  相似文献   

2.
在氯化氢无水乙醇溶液存在下,利用芳胺盐酸盐法或醛胺缩合法,4H-[1]-苯半吡埚-4-酮可直接与甲醛和芳香胺发生Mannich反应,得到3-芳氨基甲基-4H-[1]-苯并吡喃-4-酮(3)。共合成了5个未见文献报道的新化合物,产量适中。用IR,MS,^1HNMR和元素分析确定了产物(3)的结构,并对(3)的生成机理进行了讨论。  相似文献   

3.
描述双(2,2’-二羟基-1,1’-联苯)硼酸的几种改良制法和性质,2,2’-二羟基-1,1’-联苯与(MeO)3B,H3BO3-MeOH,H3BO3ak H3B·SMe2,在适宜介质中反应得到双(2,2’-二羟基-1,1’-联苯)硼酸溶剂合物,在碱存在下,它们高产率地转化为相应盐的溶剂合物,并且溶剂合物的热稳定性随溶剂极性的增加而递增。  相似文献   

4.
经实验研究发现具有结构为(C8~10H17~21)3N+CH3Cl-的季铵盐A-l是一种优良的相转移催化剂.在酯化、氧化和烷基化反应中其催化活性要优于聚乙二醇、季磷盐和其它短碳链的季铵盐.A-l在分离过程中不乳化,因而使合成产品易于分离提纯.该催化剂可循环使用,循环使用次数与温度有关.  相似文献   

5.
3,4—二氢—2H—吡喃—5—醛与脂肪二胺在水溶剂中,在冰浴下反应48h,得到2,9—二羟丙基—4,7—二氮杂—2,8—癸二烯二醛(Ⅰ)和2,10—二羟丙基—4,8—二氮杂—2,9—十一碳二烯二醛(Ⅱ),并经元素分析、红外光谱,核磁共振谱和质谱证实其结构.  相似文献   

6.
在Mg/BiCl3存在条件下,醛、酮能顺利地与炔丙基溴进行一锅法炔丙基化反应,产物或为相应的以高炔丙醇为主的高炔丙醇与丙二烯醇的混合物,或为单一高炔丙醇,当醛、酮共处于同一体系时,只有醛基发生反应,酮基则不反应。  相似文献   

7.
3,4二氢2H吡喃5醛与脂肪二胺在水溶剂中,在冰浴下反应48h,得到2,9二羟丙基4,7二氮杂2,8癸二烯二醛(Ⅰ)和2,10二羟丙基4,8二氮杂2,9十一碳二烯二醛(Ⅱ),并经元素分析、红外光谱、核磁共振和质谱证实其结构.  相似文献   

8.
醛1由NaBH4和催化氢化得醇3,经Mitsunobu反应由3合成4,4用光气处理生成异氰酸酯5,在碱的作用下,糖肟6与5缩合生成7,用氨处理并用AcSH还原酰化得目标化合物9.从葡萄糖和醛1出发,经过11步合成9,一个新的尿烷型化合物,所有的新化合物均由元素分析,红外光谱,核磁共振谱和质谱确定结构。  相似文献   

9.
1,2-二环戊二烯基四甲基二硅烷与丁基锂作用生成[四甲基二硅撑]双(环戊二烯基负离子盐),后者随即与六羰基钨反应形成1,1-[四甲基二硅撑]双[环戊二烯基三羰基钨负离子盐],(Me2SiSiMe2)·[Cp′(CO)3W-]2·2Li+(I).(I)分别与六种卤化物反应,生成在钨原子上引入取代基的产物:(Me2SiSiMe2).[Cp′W(CO)3R]2,(R:Me,C2H5,2;PhCH2,3;CH2COOC2H5,4;CH3CO,5;P3hSn,6).(I)用醋酸处理后,随即分别与CCl4,NBS及I2作用,生成相应的钨卤化物,(Me2SiSiMe2)[Cp′W(CO)3X]2,(X:C1,8;Br,9;I,10),(I)与Fe3+/H3O+作用发生氧化偶联,生成双核W-W键产物(Me2SiSiMe2)[Cp′W(CO)3]2,11.(Cp′=C5H4)  相似文献   

10.
用H4GeMo12-nWnO40mH2O(n=0~8)和甲基吡咯烷酮制备了一系列电荷转移盐,经元素分析确定其分子组成为「HMPH」4Gemo12-nWnO40CH3CN。红外光谱,紫外光谱测定结果表明在该系列固体盐中,阴离子和有机阳离子之间存在强的相互作用;光照下化合发生分子内电荷转移,阴离子发生单电子还原反应,光照变色后有杂多蓝生成;二阶非线学性质研究表明,随着化合物分子内钨取代数的增多,化合物  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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