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For the synthesis reaction of chalcone, cyclohexanone aldolization and biodiesel,γ-Al_2O_3-NaOH-Na solid superacid has a satisfactory catalytic activity. With hypnone and phenylaldehyde as raw material, amount of catalyst 7.5% wt% of material, mole ratio of hypnone and phenylaldehyde 1:1.1, reaction temperature 40℃, after 3 hours, the yield of chalcone can be up to 96.88%. With cyclohexanone as raw material, amount of catalyst 10% wt% of material, reaction temperature 190℃, after 3 hours, dimmer of cyclohexanone can be up to 85.66%.

将该固体超强碱催化剂应用于查尔酮、环己酮自缩合以及生物柴油的合成反应中,该改性固体超强碱催化剂表现出了良好的催化活性:以苯乙酮和苯甲醛为原料,反应温度为40℃,催化剂用量为反应物总质量的7.5%,苯甲醛与苯乙酮摩尔比为1:1.1,反应3h查尔酮产率可达96.88%;以环已酮为原料,催化剂用量为原料总质量的10%,反应温度为190℃,反应3h,二聚物的总收率可达85.66%;以动物油和甲醇为原料,醇油摩尔为9:1,催化剂用量为动物油质量的2%,反应温度为70℃,反应3h后,生物柴油的收率可达91.8%。

The analysis of thermal behavior and chemical structure show that the three main reactions do not initiate simultaneously. Dehydrogenization and cyclization reactions begin at the initial stage of stabilization, while oxidation reaction takes place on the precondition of cyclization reaction. Cyclization reaction has induction period that is influenced by temperature and heating rate.

热分析和化学结构分析的结果表明,预氧化过程中的三大主要反应并非同时进行,脱氢反应和环化反应从预氧化初期开始,而氧化反应需要以环化反应为前提条件,随后进行;环化反应具有一定的诱导期;在氧化性气氛中,首先发生脱氢反应,氧对环化反应起到了阻碍作用,使整个过程顺利可控。

Amino-6-nitrobenzodifuroxan was prepared through a three-step reaction from starting material 3, 5-dinitrobenzoic acid:(1)3, 5-dinitroaniline (1) was synthesized from the reaction of DNBA and hydrazoic acid in inert solvent 1, 2-dichioroethane through Schmidt rearrangement with yield of 89.6%;(2) 1 was subjected to nitration to prepare pentanitroaniline (2) with yield of 51.1%;(3) The title compound was prepared from 2 and sodium azide in acetic acid through denitrogenation and then Schmidt rearrangement with yield of 86.8%, m.p.204℃~206℃.

以3,5-二硝基苯甲酸为原料经过3步反应合成了7-氨基6-硝基苯并二氧化吠咱:第1步反应,在二氯乙烷惰性溶剂中,DNBA与叠氮酸反应并发生Schmidt重排反应生成3,5-二硝基苯胺(1),产率89.6%;第2步反应,1在含100%硫酸的硝硫混酸中硝化生成五硝基苯胺(2),产率51.1%;第3步反应,2与叠氮酸反应,不经分离直接进行热解脱氮、Schmidt重排反应,得到目标化合物, m.p.204℃~ 206℃,产率86.8%。

The dissertation mainly consists of two parts:1. The Reaction Chemistry of Alkynes under Palladium Catalysis Part 1 studies the reaction α,β-unsaturated carbonyl compounds with alkenylpalladium intermediate generated by nucleopalladation, and discovered 1 the Pd-catalyzed tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls,2 the four-component tandem addition reaction of halides, alkynes and α,β-unsaturated carbonyls, 3 the tandem intramolecular oxypalladation-conjugate additionreaction of alkynoic acids with α,β-enals. These new reactions provide notonly efficient highly stereoselective methods for the synthesis of γ,δ-unsaturated,polyunsaturated carbonyl compounds and γ-lactonic aldehydes, but also thebasic transformations for a number of C-C bond formation reactions which can be usedto design synthesis of many acyclic, cyclic or polycyclic compounds.

本论文的主要工作分为两个部分:一、钯催化下炔烃的反应化学在本小组前人工作的基础上,我们详细研究了炔烃亲核钯化产生的烯基钯中间体与α,β-不饱和羰基化合物的反应,发现两价钯催化下卤离子-炔烃-α,β-不饱和醛酮的串联加成反应、卤离子-炔烃-α,β-不饱和醛酮的西组分串联加成及炔酸分子内氧钯化-串联Michael型加成反应;由此发展了γ,δ-不饱和醛酮、多不饱和羰基化合物和带有醛酮基侧链的γ-丁内酯衍生物的高立体选择性合成方法,这一过量卤离子存在下的烯基钯对α,β-不饱和羰基化合物共轭加成反应的发现,为大量碳-碳键形成反应的实现提供了基础,使我们能够从这一基本反应出发,设计和开发多种分子内、分子间的碳碳成键反应,以好的立体、区域选择性组建开链、环状及多环类型的化合物。

Main connections are methenyl ether linkage and methenyl. From the end of heat preservation to the end of whole reaction, main reaction was polycondensation. In general, there were three types reaction among melamine modified UF resin, urea-formaldehyde system, melamine-formaldehyde system and melamine-urea-formaldehyde system.

保温反应结束直到整个反应结束,缩聚反应为主要反应类型,三聚氰胺改性脲醛树脂中存在着3种反应体系:尿素甲醛的反应体系、三聚氰胺甲醛反应体系和三聚氰铵尿素甲醛共缩合反应体系。

Study result suggest: The change of stock in RFCCU directly affect gasoline content. Gasoline content can be reduced through increasing the equilibrium activity of catalyst, controlling reaction level, increasing recirculating rate of gasoline and stability of gasoline level. Conclusions drawn from experiment is that optimization of operating condition has great effect on lowering olefine content of gasoline which can be reduced from 60% to 50%.Reducing reaction temperature is useful for lowering olefine content of gasoline, when the reaction temperature is raised, thermal cracking rate is higher than catalytic cracking rate, so that olefine content is increased. Raising catalyst-to-oil ratio is good for lowering olefine content. With conversion rate increased, the yield of LPG and coke is raised, the yield of gasoline is increased firstly and then decreased slightly, hydrogen transfer index is increased, so the olefine content is decreased.

研究结果表明:催化裂化装置的原料的变化直接影响到催化汽油的烯烃含量;可以通过优化催化装置的操作条件来降低催化汽油中的烯烃含量,其中通过提高催化剂平衡活性、控制反应深度、增加汽油回炼量、汽油深度稳定可以降低催化汽油烯烃含量,优化工艺条件对降低催化汽油烯烃含量有较大作用,汽油烯烃含量由60%降至50%左右;降低反应温度有利于降低催化汽油的烯烃含量,当反应温度的提高,热裂化反应速度提高的幅度大于催化裂化反应速度提高的幅度,汽油烯烃含量增加;剂油比的提高有利于降低催化汽油的烯烃含量,转化率提高,液化气产率提高,汽油收率先增加后略有下降,焦炭产率增加,氢转移反应指数提高,汽油烯烃含量下降;反应时间对产品分布及汽油烯烃含量有影响,增加提升管反应时间,液化汽、汽油产率提高,干气和焦炭产率增加。

The results showed that the yield of the esterification stage was 95.0% and the yield of the addition stage was 90.0% when the mole ratio of trimethylolalkane,triethyl phosphate and dimeth...

结果表明:亚磷酸三乙酯:三羟甲基丙烷:甲基磷酸二甲酯的摩尔比为1.05:1:1.2,自制复合有机酸为酯交换反应催化剂,质量分数为0.1%,反应温度85℃,反应时间3 h,自制复合有机碱为加成反应的催化剂,质量分数为1.0%,反应温度200℃,反应时间8 h,酯交换反应收率95.0%,加成反应收率90.0%。

A one-step method for the synthesis of aromatic indolizine derivatives byintramolecular 1,5-dipolar cyclization reaction of 2-(2-arylethenyl)pyridinium N-ylidesin the presence of an oxidant has been studied for the first time. In the presence ofelectron-deficient olefins, however, 2-(2-phenylethenyl)pyridinium N-ylides underwent1,3-dipolar cycloadditions and then aromatized in situ by TPCD to produce indolizinederivatives, indicating 1,3-dipolar cycloaddition proceed more readily than 1 ,5-dipolarcyclization in these conditions. Pyridinium disubstituted N-ylides, readily obtainedfrom corresponding pridinium and β-chlorovinyl ketone, underwent thermalintramolecular 1,5-dipolar cyclization to give indolizine derivatives easily.Indolizinecarbaldehyde derivatives were synthesized starting from 2-pyridinecarbaldehyde in four-steps involving 1,3-dipolar cycloaddition reaction.

本文首次研究了2-(2-芳基乙烯基)吡啶N-叶立德在氧化剂存在下的分子内1,5-偶极环化反应,采用一锅法合成了中氮茚衍生物;研究了这些N-叶立德的1,5-偶极环化和1,3-偶极环加成反应的选择性,发现当有缺电子烯烃存在时,优先进行1,3-偶极环加成反应,而不再发生分子内1,5-偶极环化反应;由β-氯乙烯酮方便地得到了烯丙基N-叶立德,他们在加热时进行分子内1,5-偶极环化反应而得到中氮茚衍生物;由2-吡啶甲醛为起始原料,通过1,3-偶极环加成反应等四步反应,得到了重要的中氮茚甲醛衍生物,这些反应都具有条件温和和操作简便的特点,是合成中氮茚衍生物的新方法。

In this article, the factors that affect molecular weight and solubility of polyacrylamide are studied and suitable initiator system is selected. The optimum parameters of copolymerizing process are obtained as follows: the molar proportion of acrylamide and sodium acrylate is 7:3, the monomer concentration is 30%, pH value of solution is 12, the oxidizer (K2S2O8) concentration is 0.1%, the reducing agent (NH2CONH2) concentration is 1%, the chain-transfer agent concentration is 0.4%. The initial reaction temperature is 35℃.

讨论了影响聚丙烯酰胺分子量和溶解性能的因素,选取了合适的氧化-还原引发体系,确定了制备超高分子量速溶型部分水解聚丙烯酰胺的优化聚合工艺参数:起始共聚合反应温度为35℃,保持在密闭条件下的共聚合反应2.5h后,再将聚合反应温度升高到55℃,继续反应2h,反应结束;反应溶液单体总浓度:30%,共聚合反应溶液pH值:12,氧化剂K_2S_2O_8:0.1%,还原剂NH_2CONH_2:1%,共聚合反应中两种单体的投料比:丙烯酰胺:丙烯酸钠=7:3,异丙醇链转移剂:0.4%。

In the step of esterification, dehydration of boric acid and then esterifying with phenol were carried out in order to increase conversion of esterification. Effect of reaction temperature, consumption of boric acid, kinds and consumption of dehydrolating agent on the yield of esterification was studied. The experimental results showed that high conversion of 98% of esterification was obtained.

本实验将酯化反应分解为脱水反应步骤和酯化反应步骤,以便提高酯化反应收率,同时,考察了反应温度、硼酸用量、带水剂种类及用量对酯化反应收率的影响,实验结果表明,该步反应条件简便易操作,反应转化率达98%。

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