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3,5-二烷氧基甲苯的溴化反应研究 总被引:1,自引:0,他引:1
3,5-二甲氧基甲苯在偶氮二异丁腈的存在下与N-溴代丁二酰亚胺(NBS)反应,产物不是3,5-二甲氧基苄溴,而是2-溴-3,5-二甲氧基甲苯和2,6-二溴-3,5-二甲氧基甲苯.同样条件下,3,5-二乙酰氧基甲苯与NBS反应则生成3,5-二乙酰氧基苄溴.GAUSSIAN 03计算的结果表明,3,5-二甲氧基甲苯中苯环碳原子上的电荷密度高于侧链上碳原子上的电荷密度,因此溴自由基更容易取代苯环上的氢,而3,5-二乙酰氧基甲苯的情况恰好相反,故产物是3,5-二乙酰氧基苄溴. 相似文献
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以邻香兰素为起始原料、经氧化裂解、付克反应及环合反应制得PDE-4抑制剂的中间体1-{8-甲氧基-2,3-二氢苯并[b][1,4]二噁烷-5-基}乙酮,总收率58.9%。 相似文献
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以三乙甘醇单甲醚为原料,制得化合物1和2; 1和2经取代反应制得1-【2-{1-[2-(2-甲氧基乙氧基)乙氧基]乙氧基}甲基-3-[2-(2-甲氧基乙氧基)乙氧基]乙氧基】丙氧基-3,5-二溴苯(3)和1-[2-(2-甲氧基乙氧基)乙氧基]乙氧基-3,5-二溴苯(4); 3和4分别与双频那醇合二硼反应制得化合物5和6; 6与5-溴-2-碘嘧啶发生Suzuki-Miyaura交叉偶联反应制得化合物7; 5与7在铂催化下发生Suzuki-Miyaura交叉偶联反应合成了一个新型的共轭大环化合物,其结构经1H NMR, 13C NMR和MALDI-TOF-MS表征。 相似文献
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以3,5-二取代异噁唑-4-甲酰肼为基本原料制备关键中间体1-(3-对甲氧基苯基-5-甲基异噁唑-4-基)-4-芳基氨基硫脲(3a~3c);3在不同条件下经关环反应制得含有3,5-二取代异噁唑的2-芳氨基噻二唑(4a~4c),2-芳氨基噁二唑(5a~5c)和3-[3′-(4"-甲氧基苯基)-5′-甲基-异噁唑4′-基)-4-芳基-1,2,4-三唑-5-硫酮(6a~6c);6与碘甲(乙)烷反应合成了4-芳基-5-[3′-(4″-甲氧基苯基)-5′-甲基异噁唑-4′-基]-3-甲(乙)硫基-1,2,4-三唑(7a~8c),其结构经1H NMR,IR,MS和元素分析表征,其中4,5,7和8未见文献报道. 相似文献
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以3,5-二甲氧基苯甲醛和吡咯为原料,经缩合反应制得meso-5,10,15,20-四(3,5-二甲氧基苯基)卟啉(1); 1与BBr-3-反应制得meso-5,10,15,20-四(3,5-二羟基苯基)卟啉(2); 2与辛酰氯反应制得meso-5,10,15,20-四[3,5-二(辛酰氧基)苯基]卟啉(3); 3分别与ZnCl2和CuCl2经配位反应合成了meso-5,10,15,20-四[3,5-二(辛酰氧基)苯基]卟啉锌配合物(4)和meso-5,10,15,20-四[3,5-二(辛酰氧基)苯基]卟啉铜配合物(5),其结构经FL, UV-Vis, 1H NMR, IR和元素分析确证。采用差示扫描量热法(DSC)和偏光显微镜研究了4和5的性能。结果表明:4和5为双变液晶,初始转变温度分别为31 ℃和28 ℃。 相似文献
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László VargaTamás Nagy István KövesdiJordi Benet-Buchholz György DormánLászló Ürge Ferenc Darvas 《Tetrahedron》2003,59(5):655-662
The reaction of chalcones and guanidine was investigated in the presence of an oxidizing agent. Depending on the order of the addition either a 4,6-diaryl-pyrimidine-2-ylamine or 2-amino-5,5-disubstituted-3,5-dihydro-imidazol-4-one was obtained. The structures of the imidazolinones were elucidated by NMR spectroscopy and X-ray crystallography and for its formation a mechanism was proposed. 相似文献
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It is shown that a mixture of 1,2,4-triazole-3,5-dicarboxylic acid and 3-methyl-1,2,4-triazole-5-carboxylic acid is formed by oxidation of 3,5-dimethyl-1,2,4-triazole with insufficient oxidizing agent. Some derivatives of 3-methyl-1,2,4-triazole-5-carboxylic acid were obtained.See [1,2] for Communication II.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1695–1696, December, 1970. 相似文献
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G. Mixich 《Helvetica chimica acta》1968,51(3):532-538
The chemical properties of the new antiphlogistic substance Mi 85 (generic name ‘Azapropazone’), which contains a 1,2,4-benzotriazine ring condensed to a 3,5-dioxo-pyrazolidine ring, were investigated. It is shown that this molecule is relatively easily attacked by various chemical reactants (scheme) mainly in the 3,5-dioxo-pyrazolidine ring and on the dimethylamino group. There are essential differences between Azapropazone and Phenylbutazone concerning their stability towards hydrolyzing and oxidizing agents. 相似文献
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Saoud A. M. Metwally Thanaa A. Mohamed Osama S. Moustafa Yasser A. El-Ossaily 《Chemistry of Heterocyclic Compounds》2007,43(9):1131-1137
Reactions of 4-alkylidene(arylidene)-1-phenylpyrazolidine-3,5-dione with oxidizing (chromium trioxide/acetic acid) as well
as with reducing (sodium borohydride/methanol) agents were carried out. Phenylhydrazine reacted with 4-arylidene-1-phenylpyrazolidine-3,5-diones
via fission of exo C=C bond to give 1-phenylpyrazolidine-3,5-dione and the corresponding aryl hydrazones.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1335–1341, September, 2007. 相似文献
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Mohammad Ali Zolfigol Arash Ghorbani Choghamarani Maliheh Safaiee Shadpour Mallakpour Mohammad Abdollahi-Alibeik 《Tetrahedron letters》2005,46(33):5581-5584
4-Substituted 1,3,4-triazole-3,5-diones were used as effective and recyclable oxidizing agents for the oxidation of 1,4-dihydropyridines to the corresponding pyridine derivatives under mild conditions with good to excellent yields. 相似文献
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An organic-soluble guanosine derivative, 2',3',5'-O-(tert-butyldimethylsilyl)guanosine (1), was prepared and its photosensitized oxidation was carried out in several solvents at various temperatures. Singlet oxygen is the reactive oxidizing agent responsible for this reaction. Neither an endoperoxide nor a dioxetane intermediate was detected by low-temperature NMR even at -78 degrees C. A product (A) with an oxidized imidazole ring was the only major product detected at room temperature; this compound could be isolated by low-temperature column chromatography and was characterized by (1)H and (13)C and mass spectroscopy. CO(2) was the other major product. A small amount of the corresponding 8-oxo-7,8-dihydroguanosine derivative B was detected during the initial stage of the photooxidation and was shown to be intermediate in the formation of two products of extensive degradation, C and D. Reaction of 1 with the singlet oxygen analogues 4-methyl-1,2,4-triazoline-3,5-dione (MTAD) and 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) gave products consistent with a proposed mechanism involving the rearrangement of an initially formed endoperoxide to give A and B from reaction of 1 with singlet oxygen. 相似文献
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Bondarenko O. B. Komarov A. I. Karetnikov G. L. Nikolaeva S. N. Zyk N. V. 《Russian Chemical Bulletin》2019,68(6):1200-1203
Russian Chemical Bulletin - It was demonstrated that nitrosylsulfuric acid can be successfully used as a tandem nitrosating and oxidizing agent in the synthesis of 3,5-diarylisoxazoles from... 相似文献
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1-O-methyl-3,5-2-O-(2,4-dichlorobenzyl)-D-ribofuranose-2-tone was produced by oxidizing 1-O-methyl-3,5-bis-O-(2,4-dichlorobenzyl)-D-ribofuranose,which was synthesized from hydroxyl protection and selectively removing O-2-protection of D-ribofuranose.Three oxidation methods,PDC,DMP and Albright-Goldman were studied in the paper.It was revealed that post-processing of PDC was harder to achieve with lots of by-products,at a yield of 39.6%.The DMP method was not suitable for industrialization due to the high cost,though the yield was as high as 91.8%.The Albright-Goldman method was the suitable oxidation method for the post-processing with its 52.0% yield.The product was characterized by MS,IR and 1HNMR. 相似文献
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