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1.
以12,-二氯乙烷为溶剂,氯化铁能有效催化邻炔基苯甲酸酯环化反应合成3-取代的异香豆素.考察了催化剂种类及用量和反应温度等因素对产率的影响,研究了不同结构底物对反应的容忍性.通过熔点测定、GC-MSI、R和NMR等手段对产物进行分析检测,表征了产物的结构.实验结果表明:当催化剂FeCl3的用量为50 mol%,以1,2-二氯乙烷作溶剂,在反应温度80℃的最佳条件下,邻苯乙炔基苯甲酸酯环化反应合成3-苯基异香豆素的产率高达96%.通过取代基对环化反应的影响研究发现,苯环上和炔烃上的官能团都不会影响反应的发生,尤其是底物的苯环上具有吸电子基团的产率要明显高于供电子基团,反应底物的适应范围比较广泛.该催化体系具有操作简单、价格低廉、选择性好等优点.  相似文献   

2.
在相转移催化剂存在的条件下,以1,2,4-三氮唑和2-氯-2′,4′-二氟苯乙酮为原料合成2′,4′-二氟-2-(1H-1,2,4-三唑-1-基)苯乙酮,分别讨论了原料配比、反应时间、缚酸剂、溶剂对合成反应的影响,确定了最佳合成工艺条件,产物收率可达82.6%。  相似文献   

3.
小分子膦催化环化反应是构建五/六元碳(杂)环的有机合成方法之一。炔酮作为缺电子反应物,可用作潜在的C2、C3、C4合成子参与环化反应,从而构建多种碳环或杂环化合物。为此,研究在叔膦催化下炔酮作为C2和C3合成子参与分子间[3+2]环化反应,生成环戊烯酮类化合物的情况。试验通过对反应催化剂、溶剂、温度及催化剂用量的考察,对反应条件进行优化。结果表明,以1,2-二氯乙烷为反应溶剂,对甲氧基三苯基膦为催化剂,在60℃条件下反应2 h,可获得良好的收率(73%)。该研究为环戊烯酮类化合物的合成提供了新方法。  相似文献   

4.
以吡咯和苯甲醛为原料合成了5-苯基-2,2′-二吡咯甲烷,利用[2+2]合成法合成了5-噻吩基-10,20-苯基-15-萘基卟啉,再利用Vilsmerier反应合成了目标化合物,目标化合物的结构经IR,MS和1 H NMR确证。考察了反应时间、物料比对目标化合物收率的影响,确定了最佳反应条件:物料比n(DMF)∶n(POCl3)∶n(化合物Ⅱ)=20∶20∶1,反应温度为以1,2-二氯乙烷为溶剂条件下的回流温度,反应时间为24h。  相似文献   

5.
在无水乙醇中,以乙醇钠为碱、2-乙酰吡啶与碳酸二甲酯为原料合成1,3,5-三酮中间体,不经纯化,继续与氨水发生关环反应,一锅法合成了4′-羟基-2,2′:6′,2″-三联吡啶,收率50%.此方法文献少见报道,合成步骤简单,产品易于纯化,收率较高.对反应收率受反应溶剂、碱性条件、反应温度、反应时间的影响进行了讨论.  相似文献   

6.
以对苯二甲酸和碘为原料,以质量分数为50%的发烟硫酸为溶剂,合成四碘对苯二甲酸,再与氯化亚砜反应得到酰氯,最后与二羟基丙基胺反应,合成N,N′双(2,3-二羟丙基)-2,3,5,6-四碘对苯二甲酰胺和N,N′(1,3-二羟丙基)-2,3,5,6-四碘对苯二甲酰胺.通过元素分析、红外光谱、核磁共振氢谱、质谱等方法证实了其结构.  相似文献   

7.
以2-乙酰基吡啶和p-甲基苯甲醛为起始原料,经过三步反应,合成了一个含有N/O的配位原子的多齿配体2,2′:6′,2″-三联吡啶-4′-苯甲酸(HL).合成该配体的中间体4′-(4-溴-苯基)-[2,2′:6′,2″]三联吡啶(L′)直接和过渡金属反应(原位合成法),通过水热法,得到了两个配合物[Co(L)2]·5H2O(1)和[Ru(L)2]·5H2O(2).晶体结构研究表明,配合物1属于三斜晶系,P-1的空间群,配合物2属于四方晶系,I41/a空间群.在两个配合物中,配体L均采用端基配位模式以三个吡啶N与金属离子螯合成环,而金属离子采用的是六配位模式,与两个配体上六个吡啶N原子配位,形成了一个扭曲的八面体结构,此外还对配体HL的红外光谱、核磁、元素分析以及两个配合物的红外光谱、紫外光谱等进行了分析讨论.  相似文献   

8.
以3-氟苯甲酸(1)为原料,通过酯化、肼解制得3-氟苯甲酰肼(2),3-氟苯甲酰肼再与芳香醛反应得到相应的酰腙(3a~3g),最后以苯和DMF为溶剂,将3a~3g与巯基乙酸脱水环化成2-芳基-3-(3-氟苯甲酰胺基)-4-噻唑啉酮类化合物(4a~4g),并利用IR、1H NMR、13C NMR、ESI-MS和元素分析对7个目标化合物(4a~4g)的结构进行了表征.用MTT方法评价了它们在体外对HepG-2、A549-1和231-23种癌细胞株的体外生长抑制活性.研究结果表明:所合成的7个新化合物均具有潜在的体外抑制癌细胞生长活性,其中化合物4a、4b、4f的活性最强.  相似文献   

9.
为了改进苏沃雷生的合成路线,简化实验操作,完善中间体理化性质及图谱数据,对其合成方法进行了研究。以2-氨基-5-甲基苯甲酸为起始原料,依次经过重氮化反应、碘代反应、Ullmann反应、酰胺化反应、脱保护反应、亲核取代反应得到目标化合物。通过优化合成方法,使用重结晶代替柱层析纯化,直接得到中间体及目标化合物。结果表明:重氮化反应和碘代反应中,以盐酸水溶液为溶剂,n(2-氨基-5-甲基苯甲酸)∶n(亚硝酸钠)∶n(碘化钾)=1∶1.2∶1.4时,收率为92.31%;Ullmann反应中,以N, N-二甲基甲酰胺为溶剂,n(2-碘-5-甲基苯甲酸)∶n(2H-1,2,3-三氮唑)∶n(碘化亚铜)=1∶2∶0.05时,收率为63.47%;脱保护反应中,以乙腈为溶剂,n((R)5-甲基-4-(5-甲基-2-(2H-1,2,3-三唑-2-基)苯甲酰基)-1,4-二氮杂-1-羧酸叔丁酯)∶n(对甲苯磺酸)=1∶1.2时,收率为93.02%;优化后,总收率为47.99%,产品纯度为99.89%,目标化合物经~1H-NMR和~(13)C-NMR得到结构确证。新的合成路线反应条件温和,实验操作及后处理简单,适合工业化生产。  相似文献   

10.
研究尼洛替尼的合成工艺及方法。以O-甲基异脲硝酸盐为原料,与3-氨基-4-甲基苯甲酸酯在醇类溶剂中反应得到3-胍基4-甲基苯甲酸酯硝酸盐,然后再和3-(二甲基氨基)-1-(3-吡啶基)-2-丙烯-1-酮环化生成嘧啶胺衍生物。在金属有机化合物存在下,中间体和3-氨基-5-溴三氟甲苯发生胺解反应得到,最后,再和4-甲基咪唑进行碳氮偶联反应得到尼洛替尼。通过1H NMR,IR和元素分析,表征了目标产物的结构,与尼洛替尼一致。该合成方法路线简捷、绿色环保、成本低、反应条件较温和。  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.
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   

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 discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

15.
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   

16.
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   

17.
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   

18.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
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   

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