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1.
为了探索在更温和,更简便的条件下有效地产生含硫碳负离子和形成新碳-碳键的方法,我们研究和发展了固-液相转移催化α-苯亚磺酰基乙酸酯的烷基化消除反应,共轭加成反应与合成戊烯二酸酯的新方法,α-芳磺酰基乙酸酯的一烷基化和二烷基化,最近又进一步研究了固-液相转移催化α-芳磺酰基乙酸脂的Michael加成。这类反应不但是构成新碳-碳键的重要方法,而且可以在产物分  相似文献   

2.
陈文华  张正 《应用化学》2007,24(8):961-964
在K2CO3-TEBA相转移催化体系中,4位或2位含有—NO2的苯磺酰基乙酸酯与α,β-不饱和酯发生加成-重排反应,制得2-芳基戊二酸酯,其收率较高(73%~87%)。研究了反应物-芳磺酰基乙酸酯苯环上取代基对加成-重排反应的影响,发现只有当芳环上4位或2位有硝基时,在K2CO3-TEBA相转移催化体系中,芳磺酰基乙酸酯与α,β-不饱和酯反应才可发生加成-重排反应,生成2-芳基戊二酸酯,其机理可能是芳磺酰基乙酸酯与α,β-不饱和酯首先发生Michael加成反应,随后加成产物发生分子内的亲核取代,酸化后脱去SO2得2-芳基戊二酸酯。而当芳环上4位或2位含有给电子基团(如,甲基)或弱吸电子基团(如,氯)时,却只能发生正常的Michael加成反应,生成相应的2-芳磺酰基戊二酸酯。  相似文献   

3.
对硝基苯磺酰基乙酸酯与芳香醛的缩合反应   总被引:1,自引:0,他引:1  
对硝基苯磺酰基乙酸酯与芳香醛在六氢吡啶醋酸盐催化下发生缩合反应生成α,β-不饱和砜,研究了催化剂对反应影响,发现DPA(3-Dimethylaminophenylpropylamine)是最有效的催化剂,可以替代六氢吡啶。在NaCl/DMSO/H2O体系中,缩合产物2-(对硝基苯磺酰基)-3-苯丙烯酸乙酯在185℃反应,得到脱羧物E-2-(对硝基)苯磺酰基苯乙烯。用1HNMR确证了缩合产物构型为E。  相似文献   

4.
本文报道在固-液相转移催化的温和条件下2-烷基-2-(芳磺酰基)乙酸酯(1)与α, β-不饱和酯、腈、酮(2)的高选择性和高效率共轭加成反应。成功地合成了2, 2-二取代戊二酸二酯(3a~d)、4-氰基丁酸酯(3e~g)和5-氧代己酸酯(3h~j)。对它们的结构作了表征。初步讨论了本合成法的特点。Michael受体、相转移催化剂和溶剂等对共轭加成反应的影响。  相似文献   

5.
冯小明  张自义 《应用化学》1993,10(1):104-106
1-酰基-4-芳基氨基硫脲类化合物在碱性条件下环化为具有广泛生物活性的3-取代基-4-芳基-1,2,4-三唑啉-5-硫酮的反应报道甚多,但1,4-位都含羰基的酰氨基硫脲在碱性条件下环化反应迄今报道较少。我们曾研究了1-[5-(α-萘)-2H-四唑-2-乙酰基]-4-芳酰基氨基硫脲和1-(α-萘乙酰基)-4-芳酰基氨基硫脲在碱催化下环化为3-取代基-4-芳酰基-1,2,4-三唑啉-5-硫酮的反应,它们在低浓度下均有一定的生物活性。本文研究了1-苯乙酰基-4-芳酰基氨基硫脲1_(a~m)在1mol/L K_2CO_3溶液催化下的环化反应,得到环化产物3-苄基-4-芳酰基-1,2,  相似文献   

6.
本文以季铵碱树脂作为聚合物固载的相转移催化剂, 在50%氢氧化钠水溶液中催化α-苯磺酰基苯乙酮(1)的α-亚甲基的烷基化反应。发现在三相催化剂存在下, 化合物1的烷基化产物与烷基化剂卤代烃的活性和反应温度有关。在非质子化溶剂HMPA存在下,50℃时发现了化合物1的α-碳和O-双烷基化的烯醇醚产物。但在100℃时只得到化合物1的分解产物苯基甲基砜而非烷基化产物。  相似文献   

7.
在K2CO3-TEBA-DNIF体系中,2-(2-氧-4-硝基苯磺酰基)-1-芳基乙酮与各种烷基化试剂发生烷基化-环化反应,得到一系列3-位取代的1,4-氧硫杂萘4,4-二氧化物,并讨论了反应机理和反应条件.  相似文献   

8.
在固液相转移催化(K2CO3/DMF/TEBA)条件下,对硝基苯磺酰基乙酸酯与α、β-不饱和酸酯反应意外地生成加成重排产物。其反应机理可能是砜酯首先与α、β-不饱和酯起Michael反应,随后加成物发生分子内芳环上的新核性取代,酸化后脱去SO2得最终产物。  相似文献   

9.
近年来相继报道,芳酰基硫脲衍生物对小麦根和苗的生长具有显著的促进生长功效,其效果优于2.4-二氯苯氧基乙酸和α-萘氧基乙酸等。为了进一步研究芳酰基硫脲类化合物的结构与生物活性之间的关系,本文于固液相转移催化剂条件下,以PEG-400为催化剂,合成了一系列N-芳酰基-N’-芳酰基硫脲衍生物。初步生物活性试验结果表明,目标化合物对小麦幼苗的生长有显著的促进功效。合成反应如下。  相似文献   

10.
芳硫基乙酸酯及其氧化产物的色谱行为(Ⅲ)──在反相高效液相色谱中的行为练鸿振,茅力,苗进,徐小青,张正(南京大学现代分析中心,化学系,南京,210093)关键词芳硫基乙酸酯;芳亚磺酰基乙酸酯;芳磺酰基乙酸酯;反相高效液相色谱在现代有机合成中,含硫有机...  相似文献   

11.
本文通过BnHn2-(n=10,12)及B3H8-盐分别与C5H5FeC5H4CH2N(R)Me2Cl和Fe(C5H4CH2N(R)Me2Cl)2(R=CH3-,C2H5-,n-C3H7-,CH2=CH-CH2-和CH≡C-CH2-)在水溶液中进行反应,合成了相应的三十个新的硼烷阴离子衍生物,这些化合物对水稳定性好,B10H102-及B12H122-衍生物对热、酸、碱和氧化剂均很稳定。研究了反应物之间的用量比例对反应产物的影响。实验结果表明,不论反应物之间的克分子比如何变化,只能得到相应的一种产物(产率90-98%)。  相似文献   

12.
The synthesis of cyclopentadienyl complexes containing polydentate C5R4(CH2CH2NMe2) ligands (R = H, Me) and Group 13 elements (Al, Ga, In) is described. The compounds (C5Me4CH2CH2NMe2) AlX2 (X = Me, Cl, Br, I), (C5Me4CH2CH2NMe2)MCl 2 (M = Ga, In), (C5H4CH2CH2NMe2)AlX2 (X = H, Me, Et, Cl), (C5H4CH2- CH2NMe2)GaCl2,and (C5H4CH2CH2NMe2)InMe2 are obtained by three different procedures. All compounds that have been characterized, so far, by X-ray diffraction studies show an additional intramolecular coordination of the nitrogen atom in the side chain. Monomeric structures and sufficient volatilities make them potential candidates for MOCVD processes.  相似文献   

13.
Carbon---hydrogen bond cleavage at the terminal 6-position occurs when hex-5-en-2-one (CH2=CHCH2CH2COMe) oxidatively adds to [Os3(CO)10(MeCN)2] to give [Os3H(μ-CH=CHCH2CH2COMe)(CO)10], which is completely analogous to the simple vinyl complex [Os3H(μ-CH=CH2)(CO)10]. A minor product from the reaction is [Os3(CH3CH=CHCH2COMe)(CO)10], an isomer in which double-bond migration has occurred to give the βγ-unsaturated ketone; stabilisation occurs through chelation and ketone coordination. [Os3H2(CO)10] reacts with CH2=CHCH2CH2COMe in refluxing cyclohexane to give a third isomer, [Os3H(CH3CH2C=CHCOMe)(CO)10], in which further double bond migration has occurred to give the β-unsaturated ketone. Metallation at the β-site gives an Os---C bond as part of a 5-membered chelate ring. Thermolysis of each of the three isomeric decarbonyl species in refluxing cyclohexane or heptane leads to the elimination of an Os(CO)4 group to give the dinuclear compound [Os2H(EtC=CHCOMe)(CO)6] in varying yield. Pathways from γδ to the βγ and finally the β unsaturated ketones may be mapped out.  相似文献   

14.
测定了过氧化辛酰(1)和过氧化己酰(2)在邻二氯苯中,分别在碘、碘乙烷、2-碘丙烷和3-溴丙烯存在下,90℃时热分解产物的1HNMR谱,观察到自由基捕获产物(RX,R=n-C7H15、n-C5H11;X=I,Br)和歧化产物(R-H)的CIDNP多重效应。讨论了过氧化酰热分解生成自由基对及相互作用的机理。  相似文献   

15.
非对称Schiff碱过渡金属配合物模拟酶催化烯烃环氧化(Ⅰ)   总被引:4,自引:0,他引:4  
研究了温和条件下以亚碘酰苯为氧源,非对称性的和对称性的Mn(Ⅲ)Schiff碱配合物[Mn(Ⅲ)(CBP-phen-Xsal)Cl,X=H,Cl,Br,NO2,CH3,OCH3]和[Mn(Ⅲ)(CBP-R-CBP)Y,R=CH2CH2-,-CH(CH3)CH2-,-C6H4-;Y=Cl,OCH3]催化非官能性烯烃苯乙烯、环己烯和α-甲基苯乙烯的环氧化反应.结果表明,非对称配合物Mn(Ⅲ)(CBP-phen-Xsal)Cl是一个良好的催化非官能性烯烃环氧化反应的催化剂体系;中心金属离子Mn(Ⅲ)的电子结合能越小,催化环氧化效果越好;对上述3种烯烃环氧化物最好收率分别达到73%、100%和92%.  相似文献   

16.
The dimethylphosphino substituted cyclopentadienyl precursor compounds [M(C5Me4CH2PMe2)], where M=Li+ (1), Na+ (2), or K+ (3), and [Li(C5H4CR′2PMe2)], where R′2=Me2 (4), or (CH2)5 (5), [HC5Me4CH2PMe2H]X, where X=Cl (6) or PF6 (7) and [HC5Me4CH2PMe2] (8), are described. They have been used to prepare new metallocene compounds, of which representative examples are [Fe(η-C5R4CR′2PMe2)2], where R=Me, R′=H (9); R=H and R′2=Me2 (10), or (CH2)5 (11), [Fe(η-C5H4CMe2PMe3)2]I2 (12), [Fe{η-C5Me4CH2P(O)Me2}2] (13), [Zr(η-C5R4CR′2PMe2)2Cl2], where R=H, R′=Me (14), or R=Me, R′=H (15), [Hf(η-C5H4CMe2PMe2)2]Cl2] (16), [Zr(η-C5H4CMe2PMe2)2Me2] (17), {[Zr(η-C5Me4CH2PMe2)2]Cl}{(C6F5)3BClB(C6F5)3} (18), [Zr{(η-C5Me4CH2PMe2)2Cl2}PtI2] (19), [Mn(η-C5Me4CH2PMe2)2] (20), [Mn{(η-C5Me4CH2PMe2B(C6F5)3}2] (21), [Pb(η-C5H4CMe2PMe2)2] (23), [Sn(η-C5H4CMe2PMe2)2] (24), [Pb{η-C5H4CMe2PMe2B(C6F5)3}2] (25), [Pb(η-C5H4CMe2PMe2)2PtI2] (26), [Rh(η-C5Me4CH2PMe2)(C2H4)] 29, [M(η,κP-C5Me4CH2PMe2)I2], where M=Rh (30), or Ir, (31).  相似文献   

17.
H CIDNP spectra recorded during the decomposition of aliphatic diacyl peroxides ((RCOO)2 R=n-C H (1),n-c5H11(2)) in ODCB in the presence of scavengers,such as I2C2H5I,(CH3)2CHI,and CH2=CHCH2 Br show multiplet effect for the scavenged products,RX(X=Br,I) and for disproportionation products,R-H.The reactionmechanism is discussed in terms of radical pair theory.  相似文献   

18.
Reactions of [C6F5Xe]+ [AsF6] in acetonitrile with halide anions X show different results depending on X. If X = I, Br or Cl, then C6F5X is obtained. If X = F, then C6F5H and C6F5---C6F5 are produced, and if X = HF2, then C6F6, C6F5H and C6F5---C6F5 are formed.  相似文献   

19.
The EI-mass spectra of the dimeric η3-allylnickel(II) halides (C3H5NiX)2 (X = Cl, Br, I) were recorded. Besides the successive splitting-off of the C3H5 groups and the elimination of C3H5X, the formation of NiX2 leading to (C3H5)2Ni is the predominating fragmentation path. Cleavage of the dimeric structure is observed only in the case where X = I.  相似文献   

20.
Theoretical calculations (DFT, MP2) are reported for up to four sets of reaction products of trimethylphosphine, (CH3)3P, each with H2O, HCl and HF together with DFT calculations on up to three sets of reaction products of substituted phosphonium cations, (CH3)3P–R+. These products comprise (a) P(III) normal complexes (CH3)3PHY, (b) P(IV) ‘reverse’ complexes Y(H–CH2)3P–R, (c) P(IV) ylidic complexes YHCH2(CH3)2P–R and (d) P(V) covalent compounds Y–P(CH3)3–R for Y=HO, Cl and F and R=H, CH3, C2H5, C2H4OH and C2H4OC:OCH3. Calculations are carried out at the B3LYP/6-31+G(d,p) level in all cases and also at the MP2/6-31+G(d,p) level for systems in which R=H. Minimum energy structures are determined for predicted complexes or structures and geometrical properties, harmonic vibrations and BSSE corrected binding energies are reported and compared with the limited experimental information available. Potential energy scans predict equilibria between covalent trigonal bipyramidal P(V) forms and reverse complexes comprising hydrogen bonded or ion pair, tetrahedral P(IV) forms separated by low potential energy barriers. Similar scans are also reported for equilibria between reverse complexes and ylidic complexes for Y=OH and R=CH3, C2H5, C2H4OH and C2H4OC:OCH3. Corrected binding energies, structures and values of harmonic modes are discussed in relation to bonding The names ‘pholine’ and ‘acetylpholine’ are suggested for phosphorus analogues to choline and acetylcholine.  相似文献   

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