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1.
以对异丙基苯甲酸为原料经酯化、还原、氧化反应合成了对异丙基苯甲醛。其中催化剂DMF加快了酯化反应速率,质子缓释剂乙醇的加入使得还原产率提高了34.5%,当以浓硫酸为质子缓释剂时,对异丙基苯甲酸可被直接还原为醇,氧化剂KMnO_4-CuSO_4·5H_2O以KMnO_4含量为50%最佳。合成方法相对安全环保,产品纯度达到了98.6%,总产率达到了73.8%(以对异丙基苯甲酸计)。目标化合物和中间产物通过~1H NMR表征。  相似文献   

2.
以间苯二酚和D,L-苹果酸为原料,经Pechmann反应、Reimer-Tiemann反应、Darzens缩合反应及Wittig反应合成了Phebalosin,总收率1.3%,其结构经~1H NMR和~(13)C NMR表征.  相似文献   

3.
Mannich型环肽的液相及固相合成比较   总被引:3,自引:0,他引:3  
为了改善肽化合物的抗酶解能力,首次介绍了3肽Pro-Pro-Tyr分子的非天然环 化反应,其中分别采用液相及固相两种合成方式组装直链肽,再经过分子内 Mannich缩合,得到以Mannich碱为桥连结构的环肽5(产率5.38%)及10(产率72. 7%)。产物结构经氨基酸组分及质谱分析证明。结果表明,固相法环合可以避免分 子间反应,因此产物收率明显高于液相法。  相似文献   

4.
2-呋喃甲酸和2-四氢呋喃甲酸分别与甲醇酯化后再与哌嗪进行结合缩合反应,分别合成了1-(2-呋喃甲酰基)哌嗪(90.6%)和1-(2-四氢呋喃甲酰基)哌嗪(92.3%),其结构经1H NMR和IR表征。  相似文献   

5.
以5-二氟甲氧基-2-巯基-1H-苯并咪唑和2-氯甲基-3,4-二甲氧基吡啶盐酸盐为原料,经缩合,氧化和成盐反应合成了泮托拉唑钠,其结构经1HNMR和MS表征。缩合,氧化和成盐反应的收率分别为88.8%,79.2%,89.7%。  相似文献   

6.
考虑缩合水的排除对反应体系的影响,用体积浓度单位推导出一个新的聚酯反应总包动力学方程,并应用到AA/HPHP和AA/NPG两个聚酯化反应的动力学研究中.研究发现,自催化聚酯反应的反应级数并不是固定值,对于AA/HPHP和AA/NPG两个聚酯化反应而言,低温时反应级数为2.5,高温时反应级数为3.0.此外,忽略缩合水的排除对聚酯化反应的动力学参数会产生较大误差.对于AA/HPHP和AA/NPG聚酯化反应,活化能相对误差分别达21.51%和11.33%;指前因子误差达到97.40%和87.96%.  相似文献   

7.
计燕萍  杨芸  高广春 《合成化学》2016,24(3):259-262
以CuI为催化剂,芳胺与多氟苯经重氮化/偶联一锅反应生成了6个多氟取代的联苯类化合物(3a~3f),收率56%~82%,其结构经1H NMR, 19F NMR和EI-MS确证。在最佳反应条件[1a 2 mmol, 20%CuI为催化剂,150%四丁基碘化铵为碘化试剂,V(DMSO):V(MeCN)=1 : 1为溶剂,于130 ℃反应4 h]下,3a收率75%。  相似文献   

8.
碱性离子液体[bmim]OH在Knoevenagel反应和Perkin反应中的应用   总被引:4,自引:0,他引:4  
李娟  孙辉  蔡晓晨  戴立益 《有机化学》2007,27(10):1296-1299
以碱性离子液体[bmim]OH作为催化剂, 在无溶剂条件下, 催化Knoevenagel反应和Perkin反应两类缩合反应. 实验结果表明, 该离子液体对Knoevenagel反应具有很高的催化活性, 一系列的芳香醛和活泼亚甲基化合物在室温条件下10~30 min内顺利完成反应, 以85%~95%的高产率生成取代烯烃产物. 离子液体经简单处理后能多次循环使用. 此外, 初步探讨了该碱性离子液体在Perkin反应中的应用.  相似文献   

9.
Six novel benzoylphenylurea chitin inhibitor derivatives were synthesized in the yields of 30%--50% from the readily available starting material chlorothalonil 1 via sequential fluorine exchange, aminolysis, hy-drolysis and acylation reactions.  相似文献   

10.
以(+)-紫苏醇2为起始原料, 经氧化、Witting、Diels-Alder和烯酮的芳构化等反应, 最终以17.7%的总收率完成了去甲基倍半萜Ligudentatin A(1)的全合成, 其中Diels-Alder和烯酮的芳构化反应为关键步骤.  相似文献   

11.
The thermodynamic properties of the reaction of amide and formaldehyde were calculated via B3LYP method when substituents chosen included CH3,CH2CH3,CH2CH2CH3,CH2CH2CH2CH3,CH(CH3)2,CH2CH(CH3)2,CH(CH3)CH2CH3 and C(CH3)3.Based on the optimization of the structures for reactants and products,the thermodynamic functions of all the species for an actual state were obtained.The thermodynamic data and the equilibrium constants were investigated within a temperature range of 300―343.15 K.The calculated results show that the reaction is exothermic and spontaneous.The trends of all thermodynamic properties are consistent with the temperature.The preferential order of the substituent effect is CH2CH(CH3)2CH(CH3)CH2CH3CH2CH2CH2CH3 CH2CH2CH3CH2CH3≈CH(CH3)2C(CH3)3≈CH3.  相似文献   

12.
Reduction of bis     
The reduction of symmetric, fully-substituted titanocene dichlorides bearing two pendant omega-alkenyl groups, [TiCl2(eta5-C5Me4R)2], R = CH(Me)CH= CH2 (1a). (CH2)2CH=CH2 (1b) and (CH2)3CH=CH2 (1c), by magnesium in tetrahydrofuran affords bis(cyclopentadienyl)titanacyclopentanes [Ti(IV)[eta1:eta1: eta5:eta5-C5Me4CH(Me)CH(Ti)CH2CH(CH2(Ti))CH(Me)C5Me4]] (2a), [Ti(IV)[eta1:eta1:eta5: eta5-C5Me4(CH2)2CH(Ti)(CH2)2CH(Ti)(CH2)2C5Me4]] (2b) and [Ti(IV)[eta1:eta1:eta5:eta5-C5Me4(CH2)2CH(Ti)CH(Me)CH(Me)CH(Ti)(CH2)2C5Me4]](2c), respectively, as the products of oxidative coupling of the double bonds across a titanocene intermediate. For the case of complex 1c, a product of a double bond isomerisation is obtained owing to a preferred formation of five-membered titanacycles. The reaction of the titanacyclopentanes with PbCl2 recovers starting materials 1a from 2a and 1b from 2b, but complex 2c affords, under the same conditions, an isomer of 1c with a shifted carbon - carbon double bond, [TiCl[eta5-C5Me4(CH2CH2CH=CHMe)]2] (1c'). The titanacycles 2a-c can be opened by HCl to give ansa-titanocene dichlorides ansa-[[eta5:eta5-C5Me4CH(Me)CH2CH2CH(Me)CH(Me)C5Me4]TiCl2] (3a), ansa-[[eta5:eta5-C5Me4(CH2)8C5Me4]TiCl2] (3b), along with a minor product ansa-[[eta5:eta5-C5Me4CH2CH=CH(CH2)5C5Me4]TiCl2] (3b'), and ansa-[[eta5:eta5-CsMe4(CH2)3CH(Me)CH(Me)CH=CHCH2C5Me4]TiCl2] (3c), respectively, with the bridging aliphatic chain consisting of five (3a) and eight (3b, 3b' and 3c) carbon atoms. The course of the acidolysis changes with the nature of the pendant group; while the cyclopentadienyl ring-linking carbon chains in 3a and 3b are fully saturated, compounds 3c and 3b' contain one asymetrically placed carbon-carbon double bond, which evidently arises from the beta-hydrogen elimination that follows the HCl addition.  相似文献   

13.
Photodissociation of 3-(methylthio)propylamine and cysteamine, the chromophores of S atom containing amino acid methionine and cysteine, respectively, was studied separately in a molecular beam at 193 nm using multimass ion imaging techniques. Four dissociation channels were observed for 3-(methylthio)propylamine, including (1) CH(3)SCH(2)CH(2)CH(2)NH(2)-->CH(3)SCH(2)CH(2)CH(2)NH+H, (2) CH(3)SCH(2)CH(2)CH(2)NH(2)-->CH(3)+SCH(2)CH(2)CH(2)NH(2), (3) CH(3)SCH(2)CH(2)CH(2)NH(2)-->CH(3)S+CH(2)CH(2)CH(2)NH(2), and (4) CH(3)SCH(2)CH(2)CH(2)NH(2)-->CH(3)SCH(2)+CH(2)CH(2)NH(2). Two dissociation channels were observed from cysteamine, including (5) HSCH(2)CH(2)NH(2)-->HS+CH(2)CH(2)NH(2) and (6) HSCH(2)CH(2)NH(2)-->HSCH(2)+CH(2)NH(2). The photofragment translational energy distributions suggest that reaction (1) and parts of the reactions (2), (3), (5) occur on the repulsive excited states. However, reaction (4), (6) occur only after the internal conversion to the electronic ground state. Since the dissociation from an excited state with a repulsive potential energy surface is very fast, it would not be quenched completely even in the condensed phase. Our results indicate that reactions following dissociation may play an important role in the UV photochemistry of S atom containing amino acid chromophores in the condensed phase. A comparison with the potential energy surface from ab initio calculations and branching ratios from RRKM calculations was made.  相似文献   

14.
The self-assembly of several cis-unsaturated carboxylic acids of the structure cis-CH3(CH2)p-1CH=CH(CH2)m-1COOH on highly oriented pyrolytic graphite (HOPG) was studied. The impact of the interior cis-CH=CH group and the molecular chain length on their self-assembled structures was considered. Due to the cis conformation of the -HC=CH- group in the interior of these molecules, they display self-assembled structures significantly different from saturated acids with all-trans configurations. As an example of the class of molecules cis-CH3(CH2)p-1CH=CH(CH2)2n-1COOH (p not equal 2n) (p=8, n=7), cis-CH3(CH2)7CH=CH(CH2)13COOH self-assembles into two kinds of enantiomer domains with opposite 2-D chirality. Due to the steric restriction of the interior cis-HC=CH group, all chains with acid groups are packed at the same side of a lamella, a head-to-head arrangement which is different from the head-to-tail packing of saturated all-trans acids. However, cis-CH3(CH2)7CH=CH(CH2)8COOH, considered as one example of the group cis-CH3(CH2)p-1CH=CH(CH2)2n-2COOH (p not equal 2n-1) (p=8, n=5), does not form any stable self-assembled domain, consistent with the molecular arrangement model. This difference in self-assembly behavior between cis-CH3(CH2)p-1CH=CH(CH2)2n-1COOH (p not equal 2n) and cis-CH3(CH2)p-1CH=CHC2n-2COOH (p not equal 2n-1) shows an odd-even chain-length effect of cis-CH3(CH2)p-1CH=CH(CH2)m-1COOH (p not equal m, m=2n or 2n-1). For another category of molecules, cis-unsaturated acids with equal numbers of all-trans carbon atoms on both sides of the cis-CH=CH group, cis-CH3(CH2)m-1CH=CH(CH2)m-1COOH (m=2n or 2n-1), display another odd-even effect. cis-CH3(CH2)7CH=CH(CH2)7COOH, one example of cis-CH3(CH2)2n-1-CH=CH(CH2)2n-1COOH (n=4), is predicted to form both an enantiomer and a nonchiral racemic structure, which is in accordance with the experimental observation of its self-assembled monolayer. However, cis-CH3(CH2)2n-2CH=CH(CH2)2n-2COOH does not form a stable self-assembled domain due to the same steric repulsion as that seen in the cis-CH3(CH2)7CH=CH(CH2)8COOH structure. These odd-even effects demonstrate that molecular self-assembly can be significantly tailored by slightly changing the molecular chain length.  相似文献   

15.
合成了5个新的二丙炔醇酯类化合物[(CO2CH2C≡CH)2(1),CH2(CO2CH2C≡CH)2,(2),(CH2CO2CH2C≡CH2)(3),(CHCO2CH2C≡CH)2,(4),C6H4-1,4-(CO2CH2C≡CH)2,(5)],并对其进行了C/H,IR和^1H NMR等表征。  相似文献   

16.
Ring closing metathesis (RCM) using Grubbs' 1st generation catalyst with cis-[L(2)Pt(CH(2)CH(2)CH[double bond, length as m-dash]CH(2))(CH(2)CH(2)CH(2)CH[double bond, length as m-dash]CH(2))] yields a platinacyclooctene which can be hydrogenated to the platinacyclooctane, L(2)Pt(CH(2))(7) [L(2) = Ph(2)PCH(2)CH(2)CH(2)PPh(2) (dppp) or Ph(2)PCH(2)CH(2)PPh(2) (dppe)] in high yield.  相似文献   

17.
郭勇  陈庆云 《化学学报》2001,59(10):1722-1729
二氟二碘甲烷(CF2I2,1)与乙烯基乙醚和Na2S2O4在DMSO和乙醇的混合溶剂中反应得3,3-二氟-3-碘丙醛的乙缩醛[ICF2CH2CH(OEt)2](3).3在锌粉的作用下发生偶联反应生成二缩醛[(EtO)2CHCH2CF2CF2CH2CH(OEt)2](5)。缩醛3或5与烯醇硅醚在SnCl4作用下发生交叉偶联反应。3在锌粉或保险粉的引下与烯醇硅醚发生加成反应。3和5分别转化成硫缩醛ICF2CH2CH(SR)2(13),(RS)2CHCH2CF2CF2CH2CH(SR)2(14)或O,S-缩醛。13消HI得1,1-二氟乙烯衍生物。  相似文献   

18.
本文报道了CH3CH=C(CH3)CH=CH2(1)、CH3C(CH,)=CHCH=CH2(2)、CH3CH=C(CH3)C(CH3)=CH2(3)、CH3C(CH3)=CHC(CH3)=CH2(4)、CH3C(CH3)=C(CH3)C(CH3)=CH2(5)和CH3CH=CHCH=CH2(6)的质谱,对其中的(1)、(3)、(5)化合物做了亚稳和高分辨测定,阐述了它们的断裂规律,提出了断裂机理。  相似文献   

19.
邻苯二酚、3,5-二叔丁基邻苯二酚分别与1,5-二氯-3-氧(杂)戊烷在碱性条件下反应, 合成了开链冠醚化合物(1a-b)。1a-b与环氧氯丙烷在氢氧化钠正丁醇中缩合, 得到相应的6-羟基二苯并-16-冠-5(2a-b)。化合物2a-b分虽与丁二酰氯、壬二酰氯在无水苯中反应, 生成了两种新的酯型双冠醚化合物3a-b; 2a-b分别与1,3-二溴丙烷、1,4-二溴丁烷、1,5-二溴戊烷、1,8-二氯-3,6-二氧(杂)辛烷及1,11-二氯-3,6,9-三氧(杂)十一烷在无水二氧六环中反应, 得到了四种新的醚型双冠醚化合物4a-e。  相似文献   

20.
In the presence of enantiopure MTBH(2)(monothiobinaphthol, 2-hydroxy-2[prime or minute]mercapto-1,1[prime or minute]-binaphthyl; 0.2 eq.) quantitative allylation of ArC([double bond]O)Me takes place with impure Sn(CH(2)CH[double bond]CH(2))(4)(prepared from allyl chloride, air-oxidised magnesium and SnCl(4)) to yield tert-homoallylic alcohols in 85-92% ee. In the same process highly purified, or commercial, Sn(CH(2)CH[double bond]CH(2))(4) yields material of only 35-50% ee. The origin of these effects is the presence of small amounts of the compounds, EtSn(CH(2)CH[double bond]CH(2))(3), ClSn(CH(2)CH[double bond]CH(2))(3) ClSnEt(CH(2)CH[double bond]CH(2))(2) in the tetraallyltin sample and the presence of traces of water (which inhibits achiral background reactions). All the triallyl and diallyl species enhance the stereoselectivity in the catalytic allylation reaction, the chlorides more so than the ethyl compound. Hydrolysis of ClSnEt(CH(2)CH[double bond]CH(2))(2) affords crystallographically characterised Sn(4)(mu(3)-O)(mu(2)-Cl)(2)Cl(2)Et(4)(CH(2)CH[double bond]CH(2))(4). Reaction of this latter compound with MTBH(2) leads to the most potent catalyst.  相似文献   

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