共查询到19条相似文献,搜索用时 672 毫秒
1.
一种新的催化剂,SnCl2·2H2O,已用于2,3-二甲基-2-丁烯与乙酐的酰化反应来制备高产率的3,3,4-三甲基-4-戊烯-2-酮
(TMP). 发现SnCl2·2H2O是室温下2,3-二甲基-2-丁烯与乙酐进行酰化反应的有效催化剂.
考察了催化剂用量、乙酐用量、反应时间和溶剂的加入等因素对该酰化反应的影响.
发现当催化剂/2,3-二甲基-2-丁烯摩尔比在0.30/1和 0.60/1之间、反应时间为2
h时,所得酰化产品的产率最高.
该酰化反应进行到完全所需的时间取决于催化剂用量和乙酐用量.
在需要加入溶剂的情况下,二氯甲烷或氯仿是一种合适的溶剂. 相似文献
2.
2,3-二甲基-2-丁烯酰化合成3,3,4-三甲基-4-戊烯-2-酮的负载ZnCl2固体催化剂 总被引:1,自引:0,他引:1
研究了负载ZnCl2的固体催化剂在2,3-二甲基-2-丁烯与乙酐酰化合成3,3,4-三甲基-4-戊烯-2-酮反应中的催化活性。结果表明,K10粘土是最好的载体,但是HY沸石、Synclyst S13(一种无定型的酸性固体)、硅胶和氧化铝也都是制备负载ZnCl2的固体催化剂的有效载体。ZnCl2的负载量和改性方法都影响负载ZnCl2的固体催化剂的催化活性。 相似文献
3.
本文研究了固体酸烷基化反应催化剂H3PO4-BF3/ZrO2及H3PO4-BF3-H2SO4/ZrO2的酸性及其结构。用指示剂法及正丁胺滴定法测定了催化剂的酸强度及酸量;用吸附吡啶的红外光谱法研究了催化剂的表面酸类型;用FT-IR、XPS、XRD、DTA-TG及TPDE等方法研究了催化剂的结构。结果表明;两种催化剂表面均只有Broensted酸,酸强度为-8.2<H0≤-5.6。H3PO4-BF3/ZrO2中,活性组分强能是以H2PO4^-:BF3的形态存在,BF3通过与H2O4^-的络合作用是催化剂的活性增强。H3PO4-BF3/ZrO2中,存在H2SO4与ZrO2的成盐作用,同时亦有可能存在H2SO4与H3PO4、BF3之间的相互作用。催化剂在下焙烧失活的主要原因是H2PO4^-失水生成P2O7^4-,使催化剂表面质子酸量大幅度降低所致。 相似文献
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5.
2,2-二(4-羟基-3,5-二硝基苯基)丙烷和2,2-二(4-羟基-3-硝基苯基)丙烷的合成 总被引:2,自引:0,他引:2
双酚A在不同的ω(HNO3)溶液中硝化可得到不同的产物。在ω(HNO3)=22%的硝酸溶液中硝化,反应温度30℃所得产物为2,2-二(4-羟基-3-硝基苯基)丙烷,在ω(HNO3)=63%的硝酸溶液中硝化,采用三段温度控制法(0℃-30℃-50℃)所得产物为2,2-二(4-羟基-3,5-二硝基苯基)丙烷。产物经柱色谱纯化后,其元素分析、IR,^1H NMR,^13C NMR和MS数据与结构相符。 相似文献
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7.
首先以2-溴-1-(2,3,4-三甲氧基)苯乙酮,四丁基铵-1H-1,2,4-三唑或咪唑为原料,分别合成了2-(1H-1,2,4-三唑-1-基)-1-(2,3,4-三甲氧基)苯乙酮(Ia)和2-(1H-咪唑0-1-基)-1-(2,3,4-三甲氧基)苯乙酮(Ib)与盐酸羟胺反应生成2-(1H-1,2,4-三唑-1-基)-1-(2,3,4-三甲氧基)苯乙酮肟和1-(1H-咪唑-1-基)-1-(2,3,4三甲氧基)苯乙酮肟,产率为63%-72%,并经元素分析,IR和1H NMR进行了表征。 相似文献
8.
3-芳基-6-(6-/8-取代-4-氯喹啉-3-基)1,2,4-三唑-[3,4-b]-1,3,4-噻二唑类化合物的合成 总被引:2,自引:0,他引:2
研究了3-芳基-4-氨基-5-巯基-1,2,4-三唑与6-/8-取代-4-羟基喹啉-3-酸在三氯氧磷催化下的反应,制得16个的3-芳基-6-(6-/8-取代-4-氯喹啉-3-基)1,2-4,-三唑[3,4-b)-1,3,4-噻二唑,新化合物的结构通过元素分析,IR,^1H NMR和MS确定,讨论了其波谱性质。 相似文献
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以4,6-二甲基-2-甲氧基-1,3-苯二甲酸二乙酯为原料,经Micheal加成、环化、溴化、消除等5步反应,合成新型的多取代2,7-萘二甲酸二乙酯。该合成路线步骤少,收率高,反应条件温和、产物中的4个新化合物的结构均经元素分析、核磁共振、红外光谱和质谱确证。 相似文献
11.
在负载H3PO4的固体上3,3,4-三甲基-4-戊烯-2-酮的催化合成 总被引:1,自引:0,他引:1
3,3,4-Trimethyl-4-penten-2-one has been synthesized by the acylation of 2,3-dimethyl-2-butene with acetic anhydride in the presence of soild-supported H3PO4.By comparison of the acylation reactions of 2,3-dimethyl-2-butene with acetic anhydride over various soilds-supported H3PO4,it was found that K10 clay,silicagel,HY zeolite and HMordenite were good supports.The results obtined indicate that the soild-supported small amounts of H3PO4 possessed higher catalytic activities,For obatining a higher yield of 3,3,4-trimethyl-4-penten-2-one different supports required different modification methods. 相似文献
12.
以H3PW12O40和AlCl3·6H2O为原料合成AlPW12O40,以此为催化剂研究苯甲醚与乙酸酐的酰基化反应,其主要产物为对甲氧基苯乙酮.采用正交试验确定酰化反应的适宜条件为:苯甲醚0.1 mol,苯甲醚与乙酸酐物质的量比为1∶1.5,催化剂用量1 g,反应时间4h,反应温度100℃,在此条件下,产品收率达到69.80%.考察了不同反应底物及不同酰化试剂对反应的影响和不同磷钨酸盐的催化效果,比较了不同加热方式对催化反应的影响.结果表明,磷钨酸铝的催化活性最好,微波加热合成目标产物效果更好. 相似文献
13.
室温下用HY沸石取代传统催化剂通过1-甲基环己烯与乙酐的酰基化反应合成了6-乙酰基-1-甲基环己烯,考察了HY沸石的SiO2/Al2O2摩尔比、用量和活化时间以及反应时间对该酰化反应的影响.当1-甲基环己烯/乙酐/HY沸石(SiO2/Al2O3摩尔比=29)=1mmol/10mmol/0.200g、反应温度25℃、反应时间3h时,所得酰化产品的产率为60%,HY沸石能够回收和重新使用,显示出与新鲜催化剂几乎相同的催化活性. 相似文献
14.
ZHAO Zhen-hua 《高等学校化学研究》2000,16(3):191-197
Introduction Friedel- Crafts acylation is one of the most important methods for synthesizing aromaticketones[1 ].Lewis acids or other catalysts are used in order to allow the reaction of anisole toproceed ata convenientrate.Forexample,the reaction of anisole with aceticanhydride in thepresence of aluminium chloride(Al Cl3/ anisole molar ratio=2 .2 / 1 ) gives4- methoxyace-tophenone in a good yield[2 ].Polyphosphoric acid(PPA/ anisole molarratio=1 3.6 / 1 ) hasalsobeen used for the react… 相似文献
15.
ZHAOZhen-Hua 《应用化学》2002,19(4):310-312
Beak et al[1 ] reported that the acylation of ethylidenecyclohexane( EDC) using zincchloride as a catalyst gave 3 -( 1 -cyclohexenyl) -2 -butanone( CHB) in good yield.However,it is pity that they provided only little information about reaction conditions,and no information on comparison of activities of various catalysts. Itis well known thatconventional Zn Cl2 catalyst leads to a great number of environmental pollution,whichcould be mainly overcome by use of the solid catalysts as we have … 相似文献
16.
ShuoWenWANG BoJieSHI YuChangLI QingMinWANG RunQiuHUANG 《中国化学快报》2004,15(3):261-264
3, 3-Dimethyl-1-(1,2,4-triazol)-2-butanone was treated with aqueous formaldehyde to give an additional product, and subsequent elimination by acetic anhydride yielded 4,4-dimethyl-2-(1,2,4-triazol)-1-penten-3-one. Further addition with substituted amines provideda series of (1,2,4-triazol)-4,4-dimethyl-3-pentanone, which were then reduced by KBH4 to obtaina series of (1,2,4-triazol)-4,4-dimethyl-3-pentanol. Their structures were confirmed by ^1HNMR and elemental analysis. The results of bioassay showed that the title products possess good fungicidal activities. 相似文献
17.
1-Aryl-2,5,7-trimethyl-4-oxo-1,4-dihydropyrido[2,3-d]pyrimidines are formed from the cyclization of N-acetyl-2-arylamino-4,6-dimethylnicotinonitriles by perchloric acid in a mixture of acetic acid and acetic anhydride. 1-Aryl-2-acetonyl-5,7-dimethyl-4-oxo-1,4-dihydropyrido[2,3-d]pyrimidines areformedonheating2-arylamino-4,6-dimethylnicotinamides with acetic anhydride. These and analogous compounds were obtained by acylation of 1-aryl-2,5,7-trimethyl-4-oxo-1,4-dihydropyrido[2,3-d]pyrimidines with acetic anhydride or benzoyl chloride.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1234–1236, September, 1992. 相似文献
18.
The acylation of benzo[b]furan-, benzo[b]thiophene, and indolyl-3-acetic acid arylamides using acetic anhydride in the presence of 70% perchloric acid occurs at the -position of the heterocycle to give 2-acetylbenzo[b]furan-, 2-acetylbenzo[b]thiophene, and 2-acetylindolyl-3-acetic acid arylamides. Depending on the amount of perchloric used in the reaction they undergo cyclodehydration to 3-arylamino-1-methylhetero[2,3-c]pyrilium salts and to N-aryl-1-methyl-3(2H)hetero[2,3-c]pyridones. 相似文献
19.
The photoaddition of 5-fluoro-4,4-dimethyl-2-cyclopentenone ( 4 ) to 2,3-dimethyl-2-butene leads specifically (in cyclohexane) and selectively (in acetonitrile) to the formation of the oxetanes 16 . The title compound is compared in its behaviour to the analogous 6-fluoro-4,4-dimethyl-2-cyclohexenone ( 1 ) and both α'-fluoro-4,4-dimethyl-2-cycloalkenones in turn are compared to the corresponding 2-cycloalkenones ( 6 and 3 ) and 4,4-dimethyl-2-cycloalkenones ( 5 and 2 ). The quantum yield for the addition of these enones to 2,3-dimethyl-2-butene and to cyclopentene are discussed. 相似文献