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1.
以双酚AF为原料,通过硝化和还原合成得到含氟苯并噁唑聚合物的单体2,2-双(4-羟基-3-氨基苯基)六氟丙烷(3)。将等摩尔量的对苯二甲酰氯与化合物3反应制得邻羟基酰胺聚合物5,然后再高温脱水环化即得到含氟聚苯并噁唑聚合物6。通过红外、质谱和核磁等表征手段确定了双酚AF的硝化产物2和含氟苯并噁唑聚合物单体3结构。邻羟基酰胺聚合物5及含氟聚苯并噁唑聚合物6的结构由红外表征确定。热重分析表明,含氟聚苯并噁唑聚合物6的5%失重温度为530℃,分解温度为573℃,具有良好的热稳定性。  相似文献   

2.
建立了一种2,5-二(4-氨基苯基)-1,3,4-噁二唑的最佳合成方法。以对硝基苯甲酸和盐酸氨基脲为原料,多聚磷酸为脱水剂,150~160℃的条件下反应2h,高收率(89%)制得中间体2,5-二(4-硝基苯基)-1,3,4-噁二唑;然后在DMF溶剂中以Na2S为还原剂,于100℃的条件下反应4h,中间体还原得到目标产物2,5-二(4-氨基苯基)-1,3,4噁二唑。此反应具有时间短、收率高且后处理简单、产物容易提纯等优点。  相似文献   

3.
以价廉易得的氟苯和戊二酸为原料,经傅-克反应、酰胺化、酮的还原、偶联和环合等数步反应合成依折麦布,总收率为7.5%.其中,用KRED238全细胞酮还原酶直接还原化合物5的羰基获得了具有S构型的羟基化合物中间体6,该步反应的收率为95%,(S)-羟基de值95.68%,还原反应的立体选择性高.该结果证实了生物催化技术应用于依折麦布合成中的可行性,为依折麦布绿色不对称合成工艺的发展提供了新的思路.  相似文献   

4.
2-巯基苯并咪唑经溴化反应得到2-溴苯并咪唑.然后与ω-溴代苯乙酮发生亲核取代反应,进一步得到中间体.最后通过Cu(Ⅰ)催化偶联关环得到产物2-苯基噁唑[3,2-a]苯并咪唑.化合物的结构通过1HNMR,13CNMR得到了证实.初步考察了溶剂、碱、配体对Cu(Ⅰ)催化偶联关环得到产物2-苯基噁唑[3,2-a]苯并咪唑反应的影响.  相似文献   

5.
2-巯基苯并咪唑经溴化反应得到2-溴苯并咪唑,然后与ω-溴代苯乙酮发生亲核取代反应进一步得到中间体,最后通过Cu(I)催化偶联关环得到产物2-苯基噁唑[3, 2-a]苯并咪唑。化合物的结构通过1HNMR,13CNMR得到了证实。在本文中,我们也初步考察了溶剂、碱、配体对Cu(I)催化偶联关环得到产物2-苯基噁唑[3, 2-a]苯并咪唑反应的影响。  相似文献   

6.
合成一种罗拉匹坦关键中间体(S)-1-((R)-1-(3,5-二(三氟甲基)苯基)乙氧基)-3-氧-2-苯基丙烷-2-基)氨基甲酸苄酯(1)。以N-Cbz-L-苯甘氨酸(2)与苯甲醛二甲缩醛(3)为原料,在三氟化硼乙醚体系中经缩合反应制得(2R,4S)-2,4-二苯基噁唑烷酮-3-甲酸苄酯(4),收率为92%;4与(S)-1-(3,5-二(三氟甲基)苯基)乙醇(5)经溴甲基化产物6在低温下发生取代反应,得到中间体7,收率为72%;7经四氢铝锂还原与碳酸氢钠水解,制得罗拉匹坦关键中间体1,两步收率为75%,反应总收率为50%。中间体及产物的结构经核磁共振和质谱确证。该法反应时间短,条件温和,操作简便,具有工业化应用前景。  相似文献   

7.
目的 研究新方法 合成N-取代-5-乙酰胺甲基-2-噁唑烷酮.方法 用苯甲醛作氨基保护荆,使环氧氯丙烷经氨解、环化两步反应后,生成中间体3-乙酰胺基-1,2-环氧丙烷.然后用氮取代氨基甲酸乙酯和中间体在催化剂存在下反应生成N-取代-5-乙酰胺甲基-2-噁唑烷酮.结果 合成了4种新化合物;3步反应总产率可达到50%;用IR,1H NMR和元素分析表征了目标化合物的结构.结论 反应条件温和,简便易行,是合成N-取代-5-乙酰胺甲基-2-噁唑烷酮较好的方法 .  相似文献   

8.
以4-羟基苯乙酸为原料,通过硝化反应、酰胺化反应、还原反应,得到关键中间体5.化合物5通过与各种取代芳基酰氯进行酰胺化,相应产物最后在对甲苯磺酸催化作用下,发生闭环反应,得到8个新型的2-芳基苯并噁唑-5-乙酰哌啶衍生物.目标化合物结构均经~1H NMR,~(13)C NMR和质谱确证.抑菌活性测试表明:大多数化合物对大肠杆菌具有一定的抑菌作用,对金黄色葡萄球菌无明显抑菌作用.  相似文献   

9.
作为光敏材料的3-苯基-2-硫代-2、4-噁唑烷二酮,或做光学增感剂直接用在电子照像感光材料和热现像感光材料,或用作照像感光材料增感染料的中间体,因此合成该化合物极为重要。我们参照拝野耕造制取3-取代-2-硫代-2、4-噁唑烷二酮的方法对该化合物进行了合成,其反应为:  相似文献   

10.
王卫娜 《科学技术与工程》2012,12(17):4250-4251,4270
利用较价廉的3-硝基-4-羟基苯甲酸在Pd/C催化下氢化还原得3-氨基-4-羟基苯甲酸,再与氯甲酸甲酯(或氯甲酸乙酯)成环得苯并[d]噁唑啉-2-酮-5-羧酸。目标化合物经1H NMR和MS确证,总收率为81.6%。该方法工艺简单,条件温和,收率较高,便于工业合成。  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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  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.
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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