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1.
微波辐射三氯化铁氧化苯偶姻合成苯偶酰   总被引:1,自引:0,他引:1  
研究微波辐射下苯偶姻合成苯偶酰的反应.结果表明,以FeCl3.6H2O为氧化剂,在微波条件下,在240W的功率下,10min即可获得很高的产率(84.8%),为一种有效的苯偶姻氧化反应新方法.  相似文献   

2.
本文以β-环糊精为相转移催化剂,以过氧化氢作氧化剂,以乙酸铁为催化剂直接催化氧化苯合成苯酚.其最佳工艺条件:在pH=3、苯5 mL、H2O212 mL,相转移催化剂β-环糊精0.1 mmol时,反应时间1.5~2 h,反应温度50℃左右,乙酸铁用量3.2 mmol.  相似文献   

3.
以苯甲醛为原料,经过自身缩合、氧化、硝化合成间二硝基苯偶酰.重点考察了硝化反应工艺条件对影响反应的因素,对反应温度、混酸浓度、反应时间等进行了优选,硝化反应的最佳条件为:苯偶酰3 g(14mmol),浓硝酸4 mL,VH2SO4:VNHO3:VH2O=9:4:4,反应温度140℃,反应时间3 h,产品收率达86.4%.目标产物的结构利用IR、MS和1HNMR进行表征.  相似文献   

4.
芳基磺酰肼在NaI/TBHP催化氧化体系下形成砜基自由基,与取代苯乙炔反应,制备炔基砜。对反应条件进行筛选,获得最优条件,即以0.7 mmol对甲基苯磺酰肼、0.5 mmol苯乙炔、1.0 mmol碘化钠(NaI)为催化剂,2.0 mmol的叔丁基过氧化氢(TBHP)为氧化剂,4.0 mL无水乙醇为溶剂,在80℃时搅拌反应8 h。研究结果表明:在此条件下,该反应底物适用性好,对芳基磺酰肼和取代苯乙炔有良好的耐受性;该反应经过磺酰基自由基与芳基乙炔进行自由基加成得到烯基自由基,然后夺取碘自由基生成(E)-β-碘代烯基砜,脱掉碘化氢得到炔基砜。  相似文献   

5.
近十多年来聚合物试剂在有机合成中应用日益广泛,国内外已有不少综述和评论.芳香醛发生苯偶姻缩合反应生成苯偶姻类化合物,进一步可制得氢化苯偶姻、脱氧苯偶姻,苯偶酰及茋等各类化合物.除少数例外,氰离子几乎是这个反应唯一的有效催化剂,一般使用碱金属氰化物,在相转移催化反应中用氰化四乙铵或  相似文献   

6.
本文对聚合物氰离子催化剂(1)在芳香醛缩合反应中的性质及应用范围进行了研究.发现了芳香醛在室温下形成苯偶姻类化合物及一步合成苯偶酰类化合物或苯偶姻苯甲酸酯类化合物的反应条件,并对有关的反应机理进行了探讨.  相似文献   

7.
采用FeC13.6H2O为催化剂,在无溶剂条件下,通过催化反应氧化苯偶姻合成苯偶酰。用红外光谱(IR)、元素分析、质谱和核磁共振谱(NMR)等手段对产物进行了表征和分析。结果表明,该方法与传统的溶液法相比较,具有无有机溶剂污染、反应速度快、反应产物易于分离、产率高和后处理简单等优点。  相似文献   

8.
以苯甲醛为原料,经过自身缩合、氧化、硝化合成间二硝基苯偶酰。重点考察了硝化反应工艺条件对影响反应的因素,对反应温度、混酸浓度、反应时间等进行了优选,硝化反应的最佳争件为:苯偶酰3g(14mmol),浓硝酸4mL,Vh2SD4:VNHO3:VH2O=9:4:4,反应温度140℃,反应时间3h,产品收率达86.4%。目标产物的结构利用IR、MS和^1H NMR进行表征。  相似文献   

9.
综述了近年来国内外由安息香氧化制备苯偶酰的方法,并对多种安息香氧化方法进行了探讨。氧化安息香合成苯偶酰的方法有两种,一种是直接氧化法,以无机化合物、有机化合物、金属有机化合物以及聚合化合物作氧化剂;另一种是间接氧化法,利用催化剂、微波辐射进行催化。其中,利用催化剂催化分子氧的方法更值得关注,为安息香制备苯偶酰化合物提供了一条绿色、有效的新途径。  相似文献   

10.
设计合成了一种新型的双咪唑鎓盐,研究了该双咪唑鎓盐催化苯甲醛合成苯偶姻的安息香缩合反应,考察了溶剂,催化剂用量、反应温度、碱的用量及不同底物对该反应的影响.结果表明:双咪唑鎓盐3能有效地催化苯偶姻缩合反应,且反应的最佳条件:温度为60℃,催化剂用量为2mmol%,50%NaOH/H2O(4.0equiv.)作碱、THF作溶剂,化学产率最高可达75%.  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.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

15.
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   

16.
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   

17.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

18.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

19.
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   

20.
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   

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