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1.
合成了两个新型方酸菁染料3和5。在催化下,2,3,3-三甲基假吲哚不需N- 烷基化,可直接与方酸反应。反应过程中发生了明显的质子转移。结晶学数据表明,分子3的整体位于同一平面;溶剂苯规则地排在方酸四碳的周围, 后者酷似电子陷肼。染料5有良好的水溶性。  相似文献   

2.
合成了两个新型方酸菁染料3和5。在酸催化下,2,3,3-三甲基假吲哚不需N-烷基化,可直接与方酸反应。反应过程中发生了明显的质子转移。结晶学数据表明,分子3的整体位于同一平面;溶剂苯规则地排布在方酸四碳环的周围,后者酷似电子陷阱。染料5有良好的水溶性。  相似文献   

3.
作为一种新型的有机功能染料,方酸染料正引起化学界的极大兴趣.由于其特殊的D-A-D结构,方酸染料在可见一近红外区有强烈的吸收和荧光发射,因而越来越多地被应用在离子检测中.本文综述了近期方酸染料化学传感器的发展和应用,分别介绍了方酸染料在阳离子识别和阴离子识别中的分子设计、作用机理及应用,重点综述了方酸染料对汞、铜和锌等...  相似文献   

4.
在RHF/STO-3G、STO-3G和3-21G(仅对ZE型)水平上,用abinitioSCF方法优化得到1,2-二硒-3,4-二硫方酸(3,4-二巯基-3-环丁烯-1,2-二硒酮)三种平面异构体的平衡构型,进一步用3-21G//STO-3G(对ZZ和EE型)方法计算总能量,发现三种平面导构体中ZZ型是最稳定构象,ZE型次之,并与1,2-二硒方酸和3,4-二硫方酸从头算结果作了比较,用abinitio数值方法在STO-3G水平上计算了三种异构体的谐振动频率.  相似文献   

5.
宋波  于浩  刘翠翠  马文辉  彭孝军 《化学学报》2010,68(24):2569-2573
以吲哚啉季铵盐为原料, 分别采用两步法和固相法合成了3种水溶性不对称吲哚方酸菁染料. 两步法为将不同N-烷基取代的2,3,3-三甲基-3H-吲哚-5-磺酸季铵盐与方酸反应, 再与另一种吲哚啉季铵盐反应制备不对称菁染料. 固相法是用对氨基苯甲酸做桥连物, 将方酸化学键连到高分子固相载体聚乙二醇上, 然后与吲哚啉季铵盐杂环母核缩合制得带有固相高分子载体的半菁, 再与另一吲哚啉季铵盐杂环母核反应切掉载体, 合成不对称菁染料. 产品用C-18反相柱进行分离提纯, 通过核磁共振氢谱和质谱对产品结构进行了表征, 测试了产品的光谱性能. 比较而言, 固相法合成不对称染料效果更好, 产率接近传统两步法的二倍, 是一种更适合的合成水溶性不对称吲哚方酸菁染料的方法.  相似文献   

6.
合成了不对称冠醚方酸碲碳菁染料和对称冠醚方酸碲碳菁染料,并探讨了对称冠醚方酸碲碳菁的合成方法及反应条件,提出了其可能的反应机理。  相似文献   

7.
设计合成了四个基于喹啉与苯胺衍生物的不对称方酸菁染料7a~7d,利用1HNMR,MS和元素分析对结构进行了表征.对中间体碘盐3a~3c的合成条件进行了探索,发现随着喹啉6位取代基吸电子能力的增强,亲核取代反应的活性降低,因此需要较为苛刻的条件.对不对称方酸菁的合成方法进行了系统研究,发现不对称方酸菁前体的接入方式是反应成败的关键,并对该不对称方酸菁的吸收光谱与光稳定性进行了系统研究.研究表明,染料的吸收半峰宽较宽,最大吸收随着溶剂极性的增加发生蓝移,表现为负溶剂化效应.光稳定性实验表明,染料的光稳定较好,且喹啉半体6位取代基吸电子能力的增加有利于染料光稳定性的增加.此外,苯胺半体氮上烷基链的长度对染料的光稳定性也有影响.  相似文献   

8.
石伟宁  徐勇前  孙世国  李红娟 《应用化学》2017,34(12):1433-1449
功能性方酸菁染料具有独特的D-A-D共轭结构,其在可见光和近红外区域有强烈的吸收和荧光发射。方酸菁染料作为近红外荧光探针母体被应用于蛋白质、氨基酸、一些生物小分子、环境污染物及金属离子等的检测。本文结合课题组近几年工作综述了方酸菁染料在蛋白质、氨基酸、生物小分子、阳离子和其它物质检测方面的应用。  相似文献   

9.
方酸染料是一种重要的有机功能材料。本文用改进的溶胶-凝胶工艺,将它均匀地掺杂到无机的SiO2凝胶薄片中,制成一种新型的有机/无机凝胶杂化物。并用吸收光谱、荧光光谱等技术研究了该方酸染料在乙醇溶液中和掺杂在SiO2凝胶网络中的光物理性能。结果发现在固、液两种介质中,其光物理性能有很大差异。方酸染料在SiO2凝胶网络中,吸收光谱和荧光发射光谱的最大峰位置比在乙醇介质中有了明显蓝移,并且吸收域值随掺杂浓度增加而增大,荧光发射强度比在乙醇介质中也有了很大增强。首次对这些现象进行了解释:认为是由于方酸染料分子被包封在SiO2凝胶网络中形成分子簇集体,它的共轭π-电子和分子构型受到刚性纳米网络微孔的限域,产生了类似于无机半导体纳米粒子的量子尺寸效应。  相似文献   

10.
用量子化学从头算法,在RHF/6-31G(d,p)水平上优化了八种不对称方酸染料的分子构型,并对它们的分子内电荷转移程度与暗衰值,光敏值和最大吸收波长的定量关系进行研究,发现不对称方酸染料的分子内电荷转移性质,是影响不对称方酸染料光导性和最大吸收波长的重要因素。  相似文献   

11.
丁渝  沈苗 《化学学报》1992,50(7):722-725
本文报道两种从5-氯-3,3-二甲基戊酸乙酯(4)合成±)-顺式-3-(二氯乙烯基)-2,2-二甲基环丙烷羟酸(±)的方法.中间体4,4-二甲基-3,4-二氢-2-吡喃酮(3)是从化合物(4)经水解皂化,酸化和氧得到3,3-二甲基戊醛酸甲酯(6),再皂化得到3,3-二甲基戊醛酸(8),然后环化得到;或者由化合物4经苯基硫醚化,氧化得到8,然后环化后得到.  相似文献   

12.
The geometrical parameters and quantum mechanical force fields (QMFF's) of 3,3-dimethyl-1-(trimethylplumbyl)cyclopropene (I), 3,3-dimethyl-1-(t-butyl)cyclopropene (II), 3,3-dimethyl-1-(trimethylsilyl)cyclopropene (III), 3,3-dimethyl-1-(trimethylgermyl)cyclopropene (IV), and 3,3-dimethyl-1-(trimethylstannyl)cyclopropene (V) were calculated at the pseudopotential (HF/SDDAll) level. Analysis of the optimised geometrical parameters was performed. The set of scale factors for correction of the pseudopotential QMFF of III was determined using its earlier well-characterised vibrational spectrum. Transferral of the set of scale factors obtained for III to the QMFF's of I, II, IV and V was followed by calculation of the fundamental vibrational frequencies. Analysis of the results for these molecules revealed some peculiarities in the vibrational frequencies obtained at the pseudopotential level.  相似文献   

13.
Dye-sensitized mesoporous TiO2 photoelectrochemical cell has attracted much interest for photoelectric conversion1,2. The most efficient charge transfer dye studied so far is Ru(dcbpy)2(NCS)2 (dcbpy=4, 4'-dicarboxy-2, 2'-bipyridine), with which IPCE of about unity has been achieved3. Considering the low cost, low toxicity, easy handling, non-metal complex dyes should also be right candidates. Here we report the highly efficient photosensitization of mesoporous TiO2 electrode with a nov…  相似文献   

14.
The quantum mechanical force fields (QMFF's) of 3,3-dimethyl-1-(tert-butyl)cyclopropene (I), 3,3-dimethyl-1-(trimethylsilyl)cyclopropene (II), 3,3-dimethyl-1-(trimethylgermyl)cyclopropene (III), and 3,3-dimethyl-1-(trimethylstannyl)cyclopropene (IV) were calculated at the HF/3-21G*//HF/3-21G* level. The set of scale factors for the correction of HF/3-21G*//HF/3-21G* QMFF of II was determined using its well-characterised vibrational spectrum. Transferral of the set of scale factors obtained for II to the QMFF's of I, III and IV and calculation of the fundamental frequencies resulted in good agreement between the calculated and previously assigned experimental frequencies of III. This again demonstrates the feasibility of transferral of a set of scale factors obtained for the correction of the QMFF of a molecule to others containing heteroatoms from the same column of the Mendeleyev Periodic Table. Thus the calculations performed permitted the accurate assignment of the fundamental vibrational frequencies in the experimental IR spectrum of IV. The vibrational frequencies of 3,3-dimethyl-1-(tert-butyl)cyclopropene (I) were also calculated from the HF/6-31G*//HF/6-31G* QMFF, scaled by the set of scale factors used previously for the HF/6-31G*//HF/6-31G* QMFF's of II and III. Regularities in the trends of some vibrational frequencies with increasing atomic number of the heteroatom are observed.  相似文献   

15.
Twenty new complexes were synthesized by reacting Co(II), Cu(II), Zn, Cr(III), Fe(III), Cd and Ag salts with 3,3-dimethyl-1-(3-methylpyrazole-5-onilidene-4)-1,2,3,4-tetrahydroisoquinoline (L1), spiro{cyclohexane-1,3"-[1-(1-phenyl-3-methylpyrazole-5-onilidene-4)-1,2,3,4-tetrahydroisoquinoline]} (L2), and 3,3-dimethyl-1-(1-phenyl-3-methylpyrazole-5-onilidene-4)-1,2,3,4-tetrahydroisoquinoline (L3). These compounds were studied by IR and electronic absorption spectroscopy. The type of coordination of their ligands was discussed on the basis of the results obtained and X-ray diffraction data for L3 and [CuL2 2 Cl2] · 2L2 obtained previously.  相似文献   

16.
Treatment of 6-amino-1,3-dimethyl-5-nitrosouracil (Ia) with dimethyl acetylenedicarboxylate (DMAD) in dimethylformamide (DMF) afforded 6,7-bis(dimethoxycarbonyl)-1,3-dimethyllumazine (II). Similarly, the reaction of 6-amino-1,3-dimethyl-5-phenylazouracil with DMAD gave also II. Hydrolysis of II with hydrochloric acid gave 1,3-dimethyllumazine-6-carboxylic acid (III). III was chlorinated with thionyl chloride and then aminated with ethanolic ammonia to give rise to 6-carbamoyl-1,3-dimethyllumazine (V). V was alternatively synthesized by the treatment of Ia with propiolamide in DMF.  相似文献   

17.
Two monomeric, five-coordinate lanthanide complexes, [bis-5,5'-(1,3-propanediyldiimino)-2,2-dimethyl-4-hexene-3-onato]samarium[2,6-bis(tert-butyl)-4-methylphenoxide] and [bis-5,5'-(1,3-propanediyldiimino)-2,2-dimethyl-4-hexene-3-onato]erbium[2,6-bis(tert-butyl)-4-methylphenoxide], were isolated from the reactions of 2,6-bis(tert-butyl)-4-methylphenol with [bis-5,5'-(1,3-propanediyldiimino)-2,2-dimethyl-4-hexene-3-onato]lanthanide[bis(trimethylsilyl)amido] (lanthanide = Er(3+) and Sm(3+)). The purified phenoxides were recovered in excellent yields and analytical purity, and the reactions proceeded cleanly without Schiff-base degradation or cluster formation. Analogously, [bis-3,3'-(1,3-propanediyldiimino)-1-phenyl-2-butene-1-onato]erbium[bis(trimethylsilyl)amido] was also directly converted to [bis-3,3'-(1,3-propanediyldiimino)-1-phenyl-2-butene-1-onato]erbium[2,6-bis(tert-butyl)-4-methylphenoxide]; however, a less sterically demanding alcohol (i.e., ethanol) yielded a neutral trinuclear oxo alkoxide species with each dianionic Schiff base asymmetrically bridging through micro-oxo interactions. In this polynuclear cluster, each symmetry-related, seven-coordinate erbium(III) ion exhibits monocapped trigonal prismatic geometry, which assembles by sharing triangular capped faces. Single-crystal X-ray diffraction revealed square-pyramidal metal coordination in each five-coordinate lanthanide ion with varied S(4) ruffling of the "square base" donor atoms and the six-membered propylene diamine chelate ring adopting the boat conformation. To contrast the effect of subtle ligand changes, we also report the synthesis and characterization of [bis-5,5'-(2,2-dimethyl-1,3-propanediyldiimino)-2,2-dimethyl-4-hexene-3-onato]samarium[bis(trimethylsilyl)amido], having gem-dimethyl substituents appended to the propylene bridge central carbon. The six-membered diamine chelate ring in this compound adopts the chair conformation without metal-hydrocarbon interaction. Also presented are qualitative activity observations and polymerization data for the polymerization of rac-lactide and epsilon-caprolactone using the five-coordinate lanthanide amidos and phenoxides.  相似文献   

18.
Various methods for synthesis of 2-methyl-5,6-(1,4,7,10,13-pentaoxatridecamethyl-ene)benzotellurazole (8) are described. Under different conditions, alkylation of compound 8 with methyl iodide gave telluronium salt 1,2-dimethyl-5,6-(1,4,7,10,13-pentaoxatridecamethylene)benzo-tellurazolium iodide (15) or quaternary ammonium salt 2,3-dimethyl-5,6-(1,4,7,10,13-pentaoxatri-decamethylene)benzotellurazolium iodide (14) in high yields, repectively. The cyanine dye 3,3'-dimethyl-5,6,5',6'-bis(1,4,7,10,13-pentaoxatridecamethylene)telluracarbocyanine iodide (16) is obtained by condensation of 14 with ethyl orthoformate in acetic anhydride. The visible absorption of the cyanine dye is also discussed.  相似文献   

19.
几个烯胺的邻硝基苯甲酰化和在酸水解中发生的重排   总被引:2,自引:0,他引:2  
铁宏  马振坤  李良助  张滂 《化学学报》1990,48(7):720-725
为了了解芳酰基化的效率和双酰基衍生物的形成, 对几个典型醛和酮的吗啉烯胺进行了邻硝基苯甲酰化的探索。丁醛和异丁醛吗啉烯胺的酰化正常, 水解分别生成55%的2-(邻硝基苯甲酰基)丁醛(2)和40%的2-(邻硝基苯甲酰基)异丁醛(3)。3-戊酮和1, 3-二甲氧基丙酮的吗啉烯胺在酰化和水解时分别生成37%和14.8%相应的β-二酮的烯醇邻硝基苯甲酸酯(4)和(5)。4和5的酸水解发生意外的1, 5-和1,3-酰基转位, 分别生成3, 5-二甲基-2, 6-双(邻硝基苯基)吡喃-4-酮(6)和2-甲氧基-2-甲氧乙酰基-1, 3-双(邻硝基苯基)-1, 3-丙二酮(7)。环戊酮和环已酮吗啉烯胺的酰化分别产生9%和34%的双酰基烯胺(9a)和(9b),逐次酸水解得到2-(邻硝基苯甲酰基)环戊酮(11a)和-环已酮(11b)。在总酰化产物的直接水解中, 11a的产率可以达到81%, 而11b只有35%。对双酰化进行了一些讨论。  相似文献   

20.
The stereoselective properties of modified thiourea organocatalysts were tested in the Friedel–Crafts alkylation of indole with 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones, which produces chiral 5-((1H-indol-3-yl)(aryl)methyl)-2,2-dimethyl-1,3-dioxane-4,6-diones. Based on a tentative reaction mechanism for ((S)-N-benzyl-2-(3-(3,5-bis(trifluoromethyl)phenyl)thioureido)-N,3,3-trimethylbutanamide organocatalysts, modifications were applied in four selected regions. Systematic structure-stereoselectivity relationship study allowed designing the best efficient organocatalyst for the investigated Friedel–Crafts alkylation of indole with 5-arylidene-2,2-dimethyl-1,3-dioxane-4,6-diones.  相似文献   

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