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(E)-6-碘-3-(2-(吡啶-2-基)乙烯基)-1-(四氢-2 H-吡喃-2-基)-1 H-吲唑是阿西替尼的关键中间体,以6-硝基-1 H-吲唑为起始原料,经过碘代、加成、偶联、还原、碘代得到目标化合物。探讨了用微波辐射加热偶联反应的问题,并对各步反应合成条件进行了优化。改进后工艺总收率达42.32%(6-硝基-1 H-吲唑为原料计),收率比文献报道值提高近5%,目标化合物和各中间体经1 H NMR和MS等确证结构。改进后的工艺降低了成本,简单可行,适合工业化生产。 相似文献
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采用在曝光前后用苯并三氮唑溶液对未增感的和硫增感的立方体溴化银乳剂涂层的处理方法,考察了苯并三氮唑在溴化银成像过程的两个阶段:曝光潜影的形成阶段和潜影中心得以放大的显影阶段的作用。有意义地发现苯并三氮唑对硫增感溴化银乳剂有明显的过增感效应。实验结果表明:1)对于未增感的立方体溴化银乳剂涂层,在曝光前吸附了苯并三氮唑后会抑制潜影的形成,但曝光后吸附了苯并三氮唑对显影有十分明显的促进作用;2)对于硫增感的立方体溴化银乳剂涂层,曝光前用苯并三氮唑溶液处理后,产生显著的过增感效应,相对感光度可提高4倍左右,在曝光后用苯并三氮唑溶液处理,随着苯并三氮唑浓度的增加对显影也有一定程度的促进作用;3)对于硫增感的溴化银涂层,先经过388mV的氧化还原缓冲液处理,再经苯并三氮唑溶液处理过的样片的感光度都要较未经绥冲液处理的提高4倍左右,这说明苯并三氮唑对硫增感乳剂产生的过增感效应只与硫敏化中心内(Ag2S)n的存在有关,与(Ag)m是否存在无关。 相似文献
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在超声辐射条件下,以1,3,3-三甲基-2-亚甲基吲哚啉和5-硝基水杨醛为原料,以甲醇为溶剂,合成了光致变色化合物1,3,3-三甲基-6'-硝基螺吲哚啉苯并吡喃,以甲醇为溶剂,在有机碱六氢吡啶存在下,将1-羟乙基-2,3,3-三甲基吲哚啉碘化物和5-硝基水杨醛通过"一锅煮"的方式,合成了光致变色化合物1-羟乙基-3,3-二甲基-6'-硝基螺吲哚啉苯并吡喃。实验证实,超声辐射显著的加快了螺吡喃类化合物的合成过程。 相似文献
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利用Maxwell-Wagner效应,采用介电损耗测定法,在10kHz—3MHz的频率范围内,研究了苯亚磺酸钠(sodium benzosulfinate,简称BSI),1-苯基-5-巯基四氮唑(1-phenyl-5-mercaptotrazole,简称PMT)和5-甲基-7-羟基-1,3,4-三氮吲(口乃木)利嗪(5-methyl-7-hydroxyl-1,3,4-triazaindolizine,简称TAI)对卤化银乳剂微晶体的离子电导率的影响。加入BSI(4.76—19.07g/M AgBr)并不引起离子电导率的降低,而加入PMT和TAI(只是0.93g/M AgBr)却使离子电导率降低2个对数单位,升高了卤化银乳剂微晶体的离子电导活化能△E和表面电位eφ_s(约升高0.12eV)。进一步的研究表明:在乳剂微晶体中所含的碘,对于TAI吸附在微晶体上所引起的离子电导率的降低具有很强的抑制作用。文中对稳定剂对于离子电导性质影响的根据进行了讨论。 相似文献
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为了研究抑制剂对银核和硫化银核的不同作用,本工作考察了1-苯基-5-巯基四氮唑(PMT)和苯并三氮唑(BTA)作为抑制剂在银核和硫化银核上物理显影的阳极抑制和解抑制效应。实验结果表明:1)PMT和BTA对Ag核和银离子过量时制得的硫化银核,Ag2S(Ag),的显影催化活性都有不同程度的抑制作用,而对硫离子过量时制得的硫化银核,Ag2S(S),无明显的抑制作用,这可能是由于过量硫离子在硫化银核上的吸附要强于这两种抑制剂;2)S2O3^2-或I^-离子的存在对BTA在Ag核上有解抑制作用,不仅可恢复甚至提高Ag核的显影催化活性,而对Ag2S核的抑制作用无明显影响;3)与BTA不同,S2O3^2-或I^-离子对PMT在Ag核上没有解抑制作用,对Ag2S(Ag)核的抑制作用还稍有增强,而对Ag2S(S)核稍有减弱;4)银溶胶中的表面增强拉曼谱(SERS)测量证实:BTA在Ag核上的吸附导致Ag核显影催化活性的下降,加入S2O3^2-或I^-离子后致使BTA的SERS信号消失则意味着BTA在银核表面的脱附。以上这些结果说明阳极抑制机理在抑制效应中有重要作用。 相似文献
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以邻氨基对硝基苯酚和对硝基苯甲酰氯为原料进行酰胺化反应,再用多聚磷酸进行环化反应,得到中间体5-硝基-2-(4-硝基苯)苯并嗯唑(NNB);中间体在77~80℃,压力为2.0-2.5MPa,Raney—Ni作催化剂条件下高压催化加氢合成了5-氨基-2-(4-氨基苯)苯并嗯唑,纯度为99.8%,总收率为81.1%。通过熔点、MS、元素分析对产品进行了结构表征。 相似文献
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在微波辐射下,以苯并咪唑为原料,通过硝化、二茂铁磺酰化等步骤,得到4种硝基苯并咪唑衍生物。通过生长速率法测定化合物抑菌活性,并与对照药剂50%多菌灵可湿性粉剂进行比较。结果表明,较优反应条件:n(2a)∶n(dcpFeSO2Cl)∶SiO2∶TBAB=1∶1.1∶0.2∶0.2,微波辐射时间5 min,辐射功率567 W。化合物3a~4b均有良好的抑菌活性和广泛的抗菌谱,与对照药剂有相似的抑菌活性,6-硝基取代的目标产物的抑菌活性优于5-硝基取代的目标产物。 相似文献
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硫敏化中心中的银原子簇的增感作用 总被引:2,自引:2,他引:0
采用一定电位范围内的氧化还原缓冲液处理单分散立方溴化银乳剂颗粒表面上的硫敏化中心和由曝光生成的潜影中心,考察银原子簇的漂白和再生后的曝光效应曲线。实验结果再一次确认硫敏化中心中存在的银原子簇对硫敏化起重要作用,而且敏化效果也与银原子簇的含量有关。为此,提出硫敏化中心是由硫化银簇与银簇组成,它们在潜影形成的过程中各起不同的作用,但都有利于提高潜影的生成效率,因而共同产生敏化效应。 相似文献
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显影抑制剂对银盐CTP版材的提高反差作用 总被引:1,自引:1,他引:0
高反差是印刷用感光材料的重要特性。本文着重研究了4种化学显影抑制剂对银盐扩散转移型CTP版材反差的影响。结果发现,硫代水杨酸、2-巯基苯并噻唑、6-硝基苯并咪唑和苯并三氮唑等单独使用时,对版材反差都有不同程度的提高作用;而硫代水杨酸与6-硝基苯并咪唑配合使用时,得到了超高反差效果。通过计算,给出了各个抑制剂最佳浓度时的反差系数值。另外,利用线性CCD技术对物理显影过程的研究表明,添加抑制剂扩大了不 相似文献
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Mark A. Plummer 《Chemical Engineering Communications》2006,193(10):1321-1331
Quantum and molecular mechanics methods were used to guide the development of a liquid extraction process for the removal of sulfur compounds from gasoline using an aqueous solvent containing n-butylamine (NBA). The calculational results suggest that the extraction mechanism was via forming micelles of NBA around single sulfur compounds. That is, micelles containing 6 to 192 molecules of NBA yielded negative formation energies. With increasing NBA amounts over the same range, total sulfur removal increased in extraction experiments. However, not all sulfur compounds were extracted simultaneously. Extraction selectivities were correlated to calculated formation energies between individual sulfur compounds and a single molecule of NBA. This suggests that extraction selectivity depended on attraction of each sulfur compound out of the gasoline to the NBA micelle wall. To provide sufficient extraction time, the number of extraction stages was investigated. The results predicted that about 10 theoretical stages would be required to achieve equal extractions of all sulfur compound types and 99+% total sulfur removal. 相似文献
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Mark A. Plummer 《Chemical Engineering Communications》2013,200(10):1321-1331
Quantum and molecular mechanics methods were used to guide the development of a liquid extraction process for the removal of sulfur compounds from gasoline using an aqueous solvent containing n-butylamine (NBA). The calculational results suggest that the extraction mechanism was via forming micelles of NBA around single sulfur compounds. That is, micelles containing 6 to 192 molecules of NBA yielded negative formation energies. With increasing NBA amounts over the same range, total sulfur removal increased in extraction experiments. However, not all sulfur compounds were extracted simultaneously. Extraction selectivities were correlated to calculated formation energies between individual sulfur compounds and a single molecule of NBA. This suggests that extraction selectivity depended on attraction of each sulfur compound out of the gasoline to the NBA micelle wall. To provide sufficient extraction time, the number of extraction stages was investigated. The results predicted that about 10 theoretical stages would be required to achieve equal extractions of all sulfur compound types and 99+% total sulfur removal. 相似文献
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《Journal of Sulfur Chemistry》2013,34(1):86-95
The treatment of alkylated nitro derivatives of indazole with stannous chloride in alkanethiol gave after coupling of the obtained amines with 4-methoxybenzenesulfonyl chloride in pyridine the new N-(4-alkylsulfanylindazol-7-yl)-4-methoxybenzene sulfonamides via the nucleophilic substitution of hydrogen in position 4 of indazole, together with the expected 4-methoxy-N-(indazol-7-yl)-benzenesulfonamides. All the newly synthesized compounds have been characterized by elemental analysis and spectroscopic data. 相似文献
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对西北某大型炼化企业炼油、化工两条污水处理流程的关键工艺环节进行水样采集,采用紫外可见光谱及吹扫捕集-气相色谱与质谱联用(GC-MS))解析了污水水样中挥发性有机成分的组成和含量的变化。共鉴定出有机物19类76种,化工污水当中的有机物(43种)相对炼油污水(32种)更加复杂。研究表明,炼油污水含较多的含硫化合物(硫醚、噻吩),是恶臭气体的主要来源;化工污水含较多的含氮化合物(硝基化合物、腈类、氰类),是氨氮及总氮的主要贡献者;芳香化合物种类多达数十种,对VOCs贡献较大。指出化工污水水解环节可产生部分醇、酮类化合物,提高后续污水可生化性。生化处理环节能去除污水中的绝大部分烷烃、烯烃、炔烃和少部分醇、酮;而芳香烃、多环芳烃、氯代烃生物降解性相对较差,生化后依旧具有残留,是污水处理COD残留的重要原因,可作为炼化特征有机污染物。提出分子水平的精细解析,能够为污水处理工艺评价提供科学依据,进而对工艺开发和工艺改进提供帮助。 相似文献
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Investigated were three types of aromatic nitro compounds: (a) a derivative of o-nitrophenol capable of forming an intramolecular hydrogen bond, (b) simple aromatic nitro compounds, and (c) the intramolecular charge transfer complexes, i.e., compounds incorporating in a single molecule the donor and the acceptor moieties, the latter substituted with the nitro groups. Samples of plasticized poly(vinyl chloride) were stabilized with these compounds and tested in an Atlas Weatherometer. The extent of degradation was determined by measuring the tensile strength, elongation, and the blue light reflectance before and after 270 and 500 hr of exposure. Samples without the stabilizers and samples containing 2,4-dihydroxybenzophenone were used as standards for comparison. Little protection was provided by simple nitro compounds. The derivative of o-nitrophenol and the donor-acceptor compounds were either better or comparable to 2,4-dihydroxybenzophenone in preserving the tensile strength and elongation. It appears that the protective ability of the derivative of o-nitrophenol was associated with the hydrogen-bonded six-membered ring whereas the protection rendered by the donor-acceptor compounds was determined by the extent of the contribution of the charge transfer states and the number of benzylic hydrogens capable of undergoing photochemical reactions. However, the mechanistic interpretation of the protective ability of the donor-acceptor compounds was complicated by the color changes occurring during the exposure. 相似文献