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1.
用二氯乙烷和硫氰化铵在水介质中反府,得到了β氯代乙基硫氰。产率55%。β氯代 乙基硫氰在水中通入氯气,得到了β氯代乙基磺酰氯。产率78%。 β氯代乙基磺酰氯在水介质中酰化苯胺或对甲基苯胺,用碳酸钠作为缚酸剂。得到了 N-乙烯砜基苯胺及N-乙烯砜基对甲苯胺。 在吡啶介质中,用β氯代乙基磺酰氯酰化对硝基苯胺,得到了N-乙烯砜基对硝基苯. 胺。 用β氯代乙基磺酰氯酰化中间体或染料上的氨基,可以得到含有H-乙烯砜基的活性 染料。  相似文献   

2.
对硝基苯磺酰基乙酸酯(1_a-e)在固-液相转移催化条件下,可以进行烷基化反应生成二烷基化产物.1_a-e 中苯环上的硝基使反应活性增加,多种类型的烷基化试剂,如溴乙烷,溴丙烯和氯苄均可与其反应得到烷基化产物。本文中合成了18种二烷基化产物,4-O_2NC_6H_4SO_2CR~1R~2CO_2R(2a-i,3a-i)。方法的优点是反应条件温和,产率高(88-98%)。  相似文献   

3.
为找到一种简便易行的方法对α-硝基酮类化合物进行合成。采用取代的苯甲酰氯和硝基甲烷为原料,经过两步反应来获得有机反应中重要的中间体α-硝基酮。结果显示,通过该方法合成了12种取代的硝基苯乙酮,其产率在68%-95%之间,结构通过1H NMR验证正确。由此可知,使用取代的苯甲酰氯和硝基甲烷为原料,可以获得相应的硝基酮,并有较为满意的产率。  相似文献   

4.
本文设计以邻硝基甲苯为原料,经过溴化反应和水解反应,两步反应得到目标产物邻硝基苯甲醛.其中溴化反应采用溴化钠为溴化剂,通氯气的条件下制备中间体邻硝基二溴苄,本文针对溴化反应的应条件进行了优化.优化后的工艺条件为n(邻硝基甲苯)∶n(NaBr)∶n(H_2O)∶n(CCl_4)=0.1∶0.2∶0.27∶1,40℃反应12 h,中间体邻硝基二溴苄产率高达84.8%,邻硝基苯甲醛的总收率为81.3%,该工艺成本低,产率高,易于工业化.  相似文献   

5.
在固—液相转移催化(K2CO3/CH3CN/TEBA)条件下,对硝基苯磺酰基乙酸酯类化合物与α-氯丙酸酯在60~80℃反应没有生成正常的烷基化产物,而得到了2-(4-硝基苯磺酰基)丙酸酯,产率30%~70%.反应机理可能是:对硝基苯磺酰基乙酸酯与α-氯丙酸酯反应时相继发生了烷基化和消除反应,消除反应生成的对硝基苯亚磺酸钾与α-氯丙酸酯反应而得到最终产物.  相似文献   

6.
以L苏氨酸为初始原料,通过与甲醇进行酯化、与甲醇氨进行氨解、与氯甲酸苄酯进行氨基保护、与甲烷磺酰氯进行羟基甲磺酰化、与氯磺酸进行磺化,在碱性条件下环合,最后加氢脱保护等7步制备得到氨曲南主环。产品经核磁共振氢谱确证为目标产物,经HPLC检测纯度为98.2%,最终收率为54.6% (以L苏氨酸计)。该合成工艺对设备要求不高,产品收率较高,易于工业化。  相似文献   

7.
氯唑西林钠是耐酶、耐酸的半合成抗生素。以邻氯苯甲醛为原料 ,经与盐酸羟胺肟化制得邻氯苯甲肟 ;它与氯气在乙醇中氯化制得邻氯苯甲肟氯的乙醇液 ,此乙醇液与乙酰乙酸乙酯在正己烷中酯化、水解制得邻氯苯甲异唑酸 (5 ) ,从邻氯苯甲肟三步收率 71.5 4%。(5 )与 POCl3 酰化制得邻氯苯甲异唑甲酰氯 ,所得的酰氯 13.2 g以丙酮 10 m l溶解 ,6 -氨基青霉烷酸 (6 - APA) 10 g悬浮于水 30 0 ml中 ,用 Na OH溶清 ,加入丙酮液反应 6 0 min,以醋酸丁酯提取 ,硫酸酸化至 p H2 .0~ p H2 .5 ,醋酸丁酯液中加入 5 m l甲醇 ,加入异辛酸钠 7.7g的醋酸丁酯液 ,即析出氯唑西林钠结晶 19.2 g,收率 90 .5 7%。此方法收率高 ,成本低 ,适合于工业化生产  相似文献   

8.
2,3-二氢苯并呋喃的合成与分析   总被引:3,自引:0,他引:3  
用苯酚和钠得到苯酚钠,苯酚钠和2-氯乙醇得到2-苯氧基乙醇,与氯化锌反应得2,3-二氢苯并呋喃, 产率50%。  相似文献   

9.
以双环戊二烯为起始原料,经Diels-Alder反应、还原反应及酯化反应,合成得到双三氟甲磺酸亚降冰片烯-5基-二甲酯.选择毒性较低、易于得到的三氟甲磺酰氯做原料,去除有毒有害吡啶试剂的使用,保证无水无氧的环境,使得反应进行更彻底,得到的产物更纯净.  相似文献   

10.
本文报道以1.3—二甲基—5—氯代吡唑经三步反应合成1.3—二甲基—4—硝基—5—磺酰氨吡唑的新路线。1.3—二甲基——4—硝基—5—氯吡唑与硫脲于乙醇中反应,于水中经氯气氯化,四氢呋喃中氨化,以良好产率生成1.3—二甲基—4—硝基—5—磺酰氨吡唑。  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.
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   

16.
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   

17.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

18.
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   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  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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