首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 187 毫秒
1.
报道了一种简便的合成取代脲基膦酸酯的通用的新方法。在二氯甲烷中,三乙胺为缚酸剂的条件下,α-氨基膦酸二苯酯与三聚光气反应形成α-异氰酸基膦酸酯2,2不经分离,直接与2-氨基(苯并)噻唑加成得到α-(2-噻唑基脲基)膦酸二苯酯3,产率55.0%-88.9%。  相似文献   

2.
利用原子转移自由基聚合(ATRP)技术合成了含不同端基取代基的偶氮苯三臂星形侧链液晶聚合物. 均苯三酚与2-溴异丁酰溴通过酯化反应制备三官能团引发剂, 引发偶氮苯单体6-[4-(4-甲氧基苯基偶氮)酚氧基]己基甲基丙烯酸酯(MMAzo)或6-[4-(4-乙氧基苯基偶氮)酚氧基]己基甲基丙烯酸酯(EMAzo)的ATRP反应. 利用核磁共振氢谱(1H NMR)、凝胶色谱(GPC)、差示扫描量热法(DSC)和偏光显微镜(POM)等手段对星形聚合物进行表征. 星形聚合物的液晶性与相应均聚物相似, 但偶氮苯端基取代基的不同导致星形聚合物的液晶性差别显著. 在紫外/可见光照射下星形聚合物呈现明显的异构化转变.  相似文献   

3.
戢得蓉  粟立丹  张成刚 《有机化学》2012,32(12):2334-2338
多甲氧基菲-9-甲酸及酯是合成娃儿藤生物碱及其类似物的关键中间体.以4-(3,4-二甲氧基苯亚甲基)-6,7-二甲氧基-3-异色酮(6)为底物,2,3-二氯-5,6-二氰基苯醌(DDQ)/CH3SO3H作为氧化体系,没有得到预期的多甲氧基菲-9-甲酸内酯(1),意外产物经核磁共振等确定为两个新的3-取代苯基香豆素2,3.进一步的实验研究显示:底物发生分子内脱氢偶联为香豆素2而非菲环化合物1,是因为异色酮6苯环A上2位取代基的存在所致,其内酯环开环化合物10以及2,3-二苯基丙烯酸(12)的对比实验印证了该取代基对脱氢偶联反应选择性的影响;异色酮6氧化偶联为香豆素2的反应机理可能为酸解开环以及途经自由基正离子的脱氢偶联,香豆素3为DDQ氧化2的前体化合物8所得.  相似文献   

4.
以熔融缩聚方法全盛了具有苯烷基侧链取代的全芳香液晶聚酯,用TG,DSC,热台偏光显微镜研究了聚酯的热性能,并讨论了取代基对聚酯热性能的影响,所有合成的聚酯均为热致型液晶,且具有较低的相转变温度。特别是当聚对苯二甲酸对苯二酚酯的两个苯环上分别取代了叔丁基和苯烷基,或取代了两个苯烷基侧链后,聚酯的熔融温度下降到225℃以下,并可在室温下溶于普通的有机溶剂中。  相似文献   

5.
我们用HMO法处理了某些1,4-双[β-(4-取代苯基)乙烯基)苯及1,4-双-[β-(4-取代苯基)乙烯基]2,5-二甲氧基苯化合物,求得了π键分子轨道的能量、电荷密度、键序及自由价。另外,最高占有轨道和最低空轨道之间的能差与其电子光谱(紫外光谱及萤光光谱)之间有较好的线性关系。两个系列的电子光谱与Hammett方程的取代基常数的绝对值之间也有较好的线性关系。  相似文献   

6.
发展了一种非金属催化下高效构筑多取代苯的新方法.以10 mol%的Cs_2CO_3为催化剂,一系列α-氰基-β-甲基烯基(杂)芳基酮可在极其温和的反应条件下与丁炔二酸酯发生[4+2]环加成/脱水芳构化苯增环反应,以62%~94%的收率生成1,2-二酯基-3-(杂)芳基-4-氰基苯衍生物.  相似文献   

7.
刘倩  赵利飞  李文红  李媛 《有机化学》2012,32(11):2122-2128
以取代苯、丁烯二酸酐、邻氨基(对氯邻氨基)苯酚为原料,合成了一系列2-酯基-1,5-苯并氧氮杂衍生物,其结构通过IR,1H NMR,MS(HRMS)及元素分析进行表征.同时,确定了一个主要副产物2-苯甲酰甲基-2H-1,4-苯并噁嗪-3(4H)-酮(6h’)的结构,提出了其可能的生成机理.研究还表明,中间体4-芳基-4-氧代-2-丁烯酸酯(4)在对甲基苯磺酸为催化剂、DMF作溶剂、回流温度下反应时主要生成目标产物2-酯基-1,5-苯并氧氮杂6,而在冰醋酸为催化剂、甲醇作溶剂、回流温度下反应时则主要生成副产物6h’.  相似文献   

8.
测定了1,4-双(取代苯乙炔基)苯(Ⅰ)和反,反-1,4-双(β-取代苯乙烯基)苯(Ⅱ)的紫外光谱、荧光光谱.用CNDO/S-CI和HMO方法对苯乙炔、二苯乙炔和(Ⅰ)及苯乙烯、1,2-二苯乙烯和(Ⅱ)的激发能进行了计算和研究.讨论了化合物结构对光谱的影响.  相似文献   

9.
以对苯二甲醚为原料,经甲酰化和溴代反应合成2,5-二甲氧基-4-溴苯甲醛(2)。以对甲氧基苯酚为原料,经烷基化、氯甲基化和Michaelis-Arbuzov反应合成亚膦酸酯(5);2和5经Horner-Wittig-Emmons反应合成了2,5-双(4′-溴-2′,5′-二甲氧基苯基乙烯基)-1-甲氧基-4-(2′-乙基己基氧基)苯(6),总收率44.7%,其结构经1HNMR,13C NMR和元素分析表征。UV-Vis和荧光光谱(FL)研究表明,6的UV-Vis和FL的λmax分别位于410 nm和479 nm,497 nm,是一种绿光的MEH-PPV型单体。  相似文献   

10.
4-氧杂-6,7-二氯庚基三甲氧基硅烷依次与二苯膦钾、气相法二氧化硅、三氯化铑作用,合成了聚-4-氧杂-6,7-双二苯膦基庚基硅氧烷铑配合物。它对烯烃与取代烯烃的硅氢化反应具有良好的催化活性。  相似文献   

11.
A green catalytic oxidation of alcohols to carbonyl compounds by oxygen was developed by using catalytic amounts of [bis(acetoxy)iodo]benzene/TEMPO/KNO2. In addition, the use of a catalytic amount of poly[4-(bis(acetoxy)iodo)]styrene led to yields (up to 99%) comparable to the non-supported hypervalent iodine reagent, while offering the advantage of an efficient recovery and the subsequent recycling of the hypervalent iodine reagent.  相似文献   

12.
This article describes the synthesis and the cation-radical polymerization (Scholl reaction) of 1,3-bis[4-(1-naphthoxy) benzoyl] benzene ( 6 ) and 1,4-bis[4-(1-naphthoxy) benzoyl]- benzene ( 7 ) initiated by FeCI3. This polymerization produced poly(ether ether ketone ketone)s (PEEKK) of number average molecular weight (M?n) up to 5400 g/mol. The synthesis of bis[4-(1-naphthoxy) phenyl] methane ( 8 ), 1,3-bis[4-(1-napthoxy) phenylmethyl] benzene ( 9 ), and 1,4-bis[4-(1-naphthoxy) phenylmethyl] benzene ( 10 ) are also described. Polyethers of M?n up to 15400 g/mol at a FeCl3/monomer molar ratio of 2/1 were obtained. An increased polymerizability of the monomers 9 and 10 containing two CH2 groups versus that of the corresponding monomers containing two carbonyl groups ( 6 and 7 ) was observed. This enhanced polymerizability was explained based on the increased nucleophilicity of monomers 9 and 10 .  相似文献   

13.
For the first time, derivatives of 1,2,4-thiadiazoles have been obtained by the reaction of [bis(acyloxy)iodo]arenes with 1-monosubstituted thioureas. 1-Acetylthiourea is subject to intermolecular azacyclization to form 3,5-bis-(acetylamino)-1,2,4-thiadiazole in reaction with [bis(acyloxy)iodo]benzene. 1-Phenylthiourea forms 3,5-bis-(phenylamino)-1,2,4-thiadiazole in a single-stage reaction with (diacetoxyiodo)benzene. The reaction of 1-phenylthiourea with [bis(trifluoroacetoxy)iodo]benzene leads to the formation of 5-imino-4-phenyl-3-phenylamino-4H-1,2,4-thiadiazoline.  相似文献   

14.
Two new diamines — [1,3-bis(5-phenyl-1,2,4-triazol-3-yl)-4,6-diamino]benzene and [1,3-di-(2-benzimldazolyl)-4,6-diamino]benzene — were synthesized from 4,6-dinitroisophthalic acid. Newheterocyclic systems — 3,5,9,11-tetraphenyl[benzo[1,2-a; 4,5-a]bis(1,2,4-triazolo[4,3-c]pyrimidine)] and 2,16-diphenyl[benzo[1,2-a;4,5-a']bis(pyrimido[1,6-a]benzimidazole)]—were obtained by reaction of the diamines with benzoyl chloride and subsequent cyclization.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1274–1277, September, 1977.  相似文献   

15.
1,3-Bis[bis(4-tert-butylphenyl)chloromethyl]benzene and 1,3-bis[bis(4-anisyl)chloromethyl]benzene were employed as regioselective capping reagents for the preparation of C-6A,C-6B-bridged, permethylated alpha- and beta-CD derivatives; isolated yields up to 55% of proximally capped, methylated CDs were obtained, thus opening the way to the straightforward preparation of a wide range of A,B-functionalised CDs. As revealed by a single crystal X-ray diffraction study, the benzene-1,3-bis[bis(4-tert-butylphenyl)methyl] spacer is perfectly suited for A,B-capping of beta-cyclodextrin.  相似文献   

16.
Pendant groups such as esters, amides, carboxylic acids, etc. have been grafted at thelower rim of call-c[41arene to produce a variety of novel ionophores'. The call-c[4]areneswith different functional groups have showed coordination diversity for alkali metalcanons2. In this paper we described the synthesis of a new calixarene derivative withpodand-armed functional group and the property as ionophore and extractant for cesiumIOn.25, 26, 27, 28-Tetrakis[2-(o-methoxyphenoxy) 3 wassynthesized f…  相似文献   

17.
Reger DL  Watson RP  Smith MD 《Inorganic chemistry》2006,45(25):10077-10087
Reactions of the arene-linked bis(pyrazolyl)methane ligands m-bis[bis(1-pyrazolyl)methyl]benzene, (m-[CH(pz)2]2C6H4, Lm), p-bis[bis(1-pyrazolyl)methyl]benzene, (p-[CH(pz)2]2C6H4, Lp), and 1,3,5-tris[bis(1-pyrazolyl)methyl]benzene (1,3,5-[CH(pz)2]3C6H3, L3) with AgX salts (pz = 1-pyrazolyl; X = BF4- or PF6-) yield two types of molecular motifs depending on the arrangement of the ligating sites about the central arene ring. Reactions of the m-phenylene-linked Lm with AgBF4 and AgPF6 afford complexes consisting of discrete, metallacyclic dications: [Ag2(mu-Lm)2](BF4)2 (1) and [Ag2(mu-Lm)2](PF6)2 (2). When the p-phenylene-linked Lp is treated with AgBF4 and AgPF6, acyclic, cationic coordination polymers are obtained: {[Ag(mu-Lp)]BF4}infinity (3) and {[Ag(mu-Lp)]PF6}infinity (4). Reaction of the ligand L3, containing three bis(pyrazolyl)methane units in a meta arrangement, with an equimolar amount of AgBF4 again yields discrete metallacyclic dications in which one bis(pyrazolyl)methane unit on each ligand remains unbound: [Ag2(mu-L3)2](BF4)2 (5). Treatment of L3 with an excess of AgBF4 affords a polymer of metallacycles, {[Ag3(mu-L3)2](BF4)3}infinity (6), with one of the bis(pyrazolyl)methane units on each ligand bound to a silver cation bridging two metallacycles. The supramolecular structures of the silver(I) complexes 1-6 are organized by noncovalent interactions, including weak hydrogen bonding, pi-pi, and anion-pi interactions.  相似文献   

18.
A dicopper(II) complex, stabilized by the bis(tpa) ligand 1,2‐bis[2‐[bis(2‐pyridylmethyl)aminomethyl]‐6‐pyridyl]ethane (6‐hpa), [Cu2(μ‐OH)(6‐hpa)]3+, was synthesized and structurally characterized. This complex catalyzed selective hydroxylation of benzene to phenol using H2O2, thus attaining large turnover numbers (TONs) and high H2O2 efficiency. The TON after 40 hours for the phenol production exceeded 12000 in MeCN at 50 °C under N2, the highest value reported for benzene hydroxylation with H2O2 catalyzed by homogeneous complexes. At 22 % benzene conversion, phenol (95.2 %) and p ‐benzoquinone (4.8 %) were produced. The mechanism of H2O2 activation and benzene hydroxylation is proposed.  相似文献   

19.
The reactions of [M3(CO)12] (M=Ru or Fe) with 1,2 bis[(diphenylphosphino)methyl]benzene diselenide (dpmbSe2) in hot toluene afford a variety of phosphine-substituted selenido carbonyl clusters. They belong to the following three families: (i) 50-electron clusters with a M3Se2 core (2, 3, 5-7), (ii) 48-electron clusters with a M3Se core (1, 8), (iii) 34-electron clusters with a M2Se2 core (4). All these species derive from the P=Se bond cleavage. Cluster 1, which contains a hydrido, a phosphido, and a carbene ligand, is produced by multiple fragmentation of the diphosphine. This fragmentation appears related to the presence of the selenido ligand on the cluster, as the reaction of [Ru3(CO)12] with dpmb (not selenized) produces only carbonyl substitution by the phosphine to give [Ru3(CO)10(mu-dpmb)] (9). All the clusters synthesized have been characterized by spectroscopic techniques, and in some cases fluxional behavior has been detected in solution by NMR analysis. The structures of 1, 2, and 7-9 have been determined by X-ray diffraction methods.  相似文献   

20.
Thermolysis of trans-chloro(2-allylphenyl)bis(triethylphosphine)nickel(II), I, in tetrachloroethylene has afforded indene as the major hydrocarbon product along with lesser amounts of allylbenzene and trans-β-methylstyrene. Organonickel products were trans-chloro(trichlorovinyl)bis(triethylphosphine)nickel(II), II, chloro[2-(trans-propenyl)phenyl]bis(triethylphosphine)nickel(II), III, and trans-dichlorobis(triethylphosphine)nickel(II). Compound III was the major product from thermolysis of I in benzene. Chloro[2-(cis-propenyl)phenyl]bis(triethylphosphine)nickel(II), IV, and III could be synthesized independently by treatment of chloro-2-(cis-propenyl)benzene and chloro-2-(trans-propenyl)benzene, respectively, with nickel acetylacetonate and triethylaluminium in the presence of triethylphosphine. Thermolysis of I in benzene containing allylbenzene led to the formation of trans-β-methylstyrene. The thermolysis of I in benzene in the presence of cis-1,4-hexadiene caused the skeletal rearrangement of the diene to trans-2-methyl-1,3-pentadiene. A catalyst derived from ethylenebis(triphenylphosphine)nickel(0) and hydrogen chloride isomerized allylbenzene to trans-β-methylstyrene.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号