基于内容的乳腺X线影像钙化病灶检索技术研究.pdf

氧化钙催化的Aldol反应
摘要:本实验通过使用不同的催化剂对羟醛缩合反应进行催化,考察反应过程中在不同的反应时间,反应温度以及催化剂用量对反应产率,反应速度的影响。通过实验发现,用氧化钙作催化剂时的反应效果,要远远好于其他的酸碱,而且加热回流条件下,20%的崔化剂用量,且醛酮比例为1:,。再者就是研究同一种催化家对不同Aldol反应的影响,也是从反应速率,反应物得产率等几个方面进行分析。
以溴化苄为改性剂对氧化钙进行改性,配制不同比例的溴化苄的干燥的甲醇溶液。,加热回流3h。然后抽滤取干燥改性好的CaO。通过试验发现,改性剂的用量为万分之零点一时为最优比例。反应物产率可达95%,且反应时间明显缩短。再用甲醇作为改性剂研究甲醇对氧化钙的影响,发现最佳条件下时的产率只有60%,所以可以忽略。认为溴化苄在一定条件下确实是优化了氧化钙的催化作用。
关键词: Aldol反应,氧化钙,溴化苄
Aldol reaction catalyzed by calcium oxide
Abstract: In this study by using different catalysts on the aldol reaction catalyzed reaction process investigated at different reaction time, reaction temperature and catalyst on the reaction yield, reaction rate. Experimental results show that calcium oxide as a catalyst with the reaction when the effect is much better than the other acid, and heated under reflux, 20% of the CUI of the dosage, and the ratio of 1:1. 3 aldehydes and ketones. When the reaction 4. 5 hours or so to be plete reaction. Furthermore, is home of the same catalytic effect of different Aldol reaction, but also from the reaction rate, the yield of the reactants have to analyze several aspects.
Benzyl bromide as modifier to the modification of calcium oxide,Preparation of different ratios of dry benzyl bromide in methanol. 15ml take of calcium oxide solution and mixed reflux 3h. Modified to take a good filtration and then dried CaO. The experiment showed that the amount of modifier is extremely short of the optimal ratio of zero. Response rate of 95% of the property, and the reaction time was significantly shortened. Methanol and then methanol as a modifier of calcium oxide, and found that under optimum conditions the yield when only 60%, so can be ignored. That under certain conditions,benzyl bromide is really optimized calcium oxide catalyst.
Keywords: Aldol reaction of aldehydes and ketones, calcium oxide, benzyl bromide
目录
1 绪论…………………………………………………………………………. 1
1. 1 Aldol反应的定义……………………………………………………1