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以摩尔比为1∶2的3,4 己二酮和溴为原料,在35~40℃下反应合成了重要香原料2,5 二甲基 4 羟基 3(2H) 呋喃酮的关键中间体2,5 二溴 3,4 己二酮,产率达到805%。产品经溴元素分析、红外光谱和核磁共振分析证实了它的结构。 相似文献
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N—甲基—2,4—二硝基—N—(2,4,6—三溴苯基)—6—(三氟甲基)苯胺的合成 总被引:1,自引:0,他引:1
N甲基2,4二硝基N(2,4,6三溴苯基)6(三氟甲基)苯胺,溴杀灵,是新型一次投饵的速效杀鼠剂,它由2氯3,5二硝基三氟甲苯与苯胺偶联,再经一次溴化、二次溴化合成。总收率53.3%,纯度95%。 相似文献
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以环戊二烯二聚体、顺丁烯二酸酐、溴、乙二胺为主要原料,经五步反应合成了N,N′ 1,2 乙烷 双[5,6 二溴降冰片烷 2,3 二酰亚胺](Ⅰ)。其中前四步反应与文献[1]相同,第五步反应,取225gN,N′ 1,2 乙烷 双[5,6 二溴 3 羧基 降冰片烷 2 酰胺](Ⅱ)于三口烧瓶中,加入85ml二甲苯、32ml丙酸、4滴磷酸,加热、搅拌回流脱水5h,冷却、过滤,依次用甲苯—丙酸混合液和2%NaOH水溶液洗涤,干燥,得198g白42色固体,产率85%,与文献[1]相当。新的合成方法操作条件好,产品色泽好,成本低。提出了第五步反应可能的机理。 相似文献
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本文探讨了2-乙酰基-7-甲胺基卓酮与3,4,5-三甲氧基苯甲醛(TMB)等取代芳香醛的羟醛缩合反应。2-乙酰基-7-甲胺基卓酮与TMB、丁香醛、二溴醛等取代芳香醛进行反应分别生成了2-(3,4,5-三甲氧基)肉桂酰基-7-甲胺基卓酮;2-(4-羟基-3,5-二甲氧基)肉桂酰基-7-甲胺基卓酮;2-(4-羟基-3,5-二溴)肉桂酰基-7-甲胺基卓酮等三种尚未见文献报道的新化合物。它们的结构经红外光谱、核磁共振谱及元素分析得以证实。 相似文献
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对由2,4 二氯 5 硝基酚合成1 三甲乙酰基 2 (2,4 二氯 5 羟基苯基)肼进行了研究,四步合成总收率为58%(以2,4 二氯 5 硝基酚计)。产物是合成除草剂和恶草酮的重要中间体。化合物经红外光谱和元素分析证实了结构 相似文献
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研究了新型阻燃剂5,6,7,8-四溴-1,2,3,4-四氢化萘(TBT)的合成方法,并对工艺条件进行了研究。总收率可达50.3%。 相似文献
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Electrical properties, such as dissipation factor and electric conductivity, were studied for silicone rubber sheets. The specimens were prepared by the reaction of α,ω-dihydroxypolysiloxane with ethoxysilane, using dibutyltin dilaurate as a catalyst, at a relative humidity of about 100% at various temperatures and for various reaction times. It was found that the electrical properties were a function of the vulcanizing conditions; i.e., the further the vulcanization proceeded, the higher the dissipation factor and the electric conductivity. A reaction describing deterioration in electrical properties was then considered. Infrared spectroscopic studies on dibutyltin dilaurate showed that the dibutyltin dilaurates were partly hydrolyzed to lauric acid and dibutyltin dihydroxide. It was concluded that electrical property deteriorations, which were caused by changes in the vulcanizing conditions, were due to dibutyltin dilaurate hydrolysis. However, since the decomposed products were finally oxidized at elevated temperatures in an oxygen atmosphere, with a subsequent change to electrically inactive compounds, the initial electrical properties were recovered. 相似文献
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Role of sulfonic acids in the Sn-catalyzed transesterification of dimethyl carbonate with phenol 总被引:6,自引:0,他引:6
Hyunjoo Lee Sung Joon Kim Byoung Sung Ahn Won Koo Lee Hoon Sik Kim 《Catalysis Today》2003,87(1-4):139-144
Diphenyl carbonate, the key intermediate of the non-phosgene polycarbonate manufacturing process, can be produced by the transesterification of dimethyl carbonate with phenol in the presence of dibutyltin oxide. The use of an alkyl or aryl sulfonic acid in conjunction with dibutyltin oxide significantly enhances the activity of dibutyltin oxide. 19F and 119Sn NMR studies suggest the formation of tin complex containing strongly electrophilic sulfonate ligand from the reaction of dibutyltin oxide with alkyl or aryl sulfonic acid. Various factors affecting the transesterification of dimethyl carbonate with phenol were investigated. 相似文献
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阻燃大豆蛋白纤维的热性能研究 总被引:2,自引:0,他引:2
为了提高阻燃性,用四溴酞酐(TBPA)加有机二酸体系对大豆蛋白纤维进行了阻燃处理,然后用极限氧指数(LOI)、剩炭率表征了它的阻燃性能,用热分析和扫描电子显微镜研究了它的热性能。结果表明:与纯大豆蛋白纤维相比,阻燃处理后的大豆蛋白纤维的极限氧指数和剩炭率提高,热分解起始温度降低,阻燃性能得到了明显改进。 相似文献
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Layered double hydroxides (LDHs) have attracted much attention as nanofillers in polymer nanocomposites (NCs) due to their particular surface structural, positively charged layer and so on. In this study, a chiral diacid was synthesized by the reaction of tetrabromophthalic anhydride and glutamic acid. LDH was modified by co‐precipitation of aluminum nitrate, magnesium nitrate, and glutamic acid containing diacid. Chiral poly(amide‐imide) (PAI) was synthesized by direct polycondensation reaction of N‐trimellitylimido‐l ‐leucine and 4,4′‐diaminodiphenylether. Different NCs of the obtained modified LDHs and the chiral PAI were prepared in a short time using ultrasonic technique. The morphology and the structure of the obtained samples were characterized by Fourier transform infrared, thermogravimetric analysis (TGA), field emission scanning electron microscopy, transmission electron microscopy, and X‐ray diffraction analysis. TGA of the NCs showed a special order in thermal stability in compression with the neat PAI owing to the uniform distribution of the nanofillers. POLYM. COMPOS., 37:1323–1329, 2016. © 2014 Society of Plastics Engineers 相似文献