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1.
以脱镁叶绿酸-a甲酯(1)为起始原料, 利用其3-位乙烯基与重氮甲烷的1,3-偶极环加成反应, 得到3-位氢化吡唑取代的脱镁叶绿酸-a衍生物2, 通过热裂解使得3-位吡唑基开环并重排成环丙基. 碱性条件下, 所生成的3-环丙基取代的卟吩3脱甲氧甲酰基后转化成焦脱镁叶绿酸衍生物4. 选用重氮乙烷为另一偶极体与1进行1,3-偶极环加成反应, 则给出2-甲基环丙基取代的立体异构体卟吩5, 同样经过脱甲氧甲酰基处理, 得到焦脱镁叶绿酸衍生物6. 所合成新叶绿素衍生物26均经UV, IR, 1H NMR及元素分析证明其结构.  相似文献   

2.
以焦脱镁叶绿酸-a甲酯(1)为起始原料, 通过E环保护和3-位乙烯基的氧化反应得到卟吩醛2, 与长链烷基溴化镁的Grignard反应将3-位甲酰基转化为1-羟长链烷基, 选用TPAP和N-甲基吗啉N-氧化物混合氧化剂对卟吩仲醇3的羟基进行氧化, 生成3-位烷酰基焦脱镁叶绿酸-a衍生物4, 再与长链烷基溴化镁进行Grignard反应, 得到亲核加成产物卟吩叔醇5和还原产物3; 以对甲苯磺酸催化, 卟吩醇35在干燥苯中回流脱水, 分别给出反式结构的3-位长链烷基单或者双取代的焦脱镁叶绿酸-a甲酯衍生物67. 所合成的叶绿酸衍生物均经UV, IR, 1H NMR及元素分析证明其结构.  相似文献   

3.
单加成环丙烷富勒烯膦酸酯衍生物的合成与电化学性能   总被引:1,自引:0,他引:1  
在Mn(OAc)3•2H2O催化下, C60分别和亚甲基二膦酸四乙酯、氰基亚甲基膦酸二乙酯或乙氧羰基亚甲基膦酸二乙酯在氯苯中回流, 生成3个单加成环丙烷富勒烯膦酸衍生物C60C(R)PO(OEt)2 [1, R=PO(OEt)2; 2, R=COOEt; 3, R=CN]. 与以前报道的Bingel反应法相比, 该方法副产物少并且缩短了反应时间. 采用循环伏安法发现1, 2的还原电位相对于C60发生负移, 而3的还原电位相对于C60却正移40 mV, 表明引入象氰基一样具有很强吸电子能力的取代基团, 可以改善富勒烯球的电化学性能, 合成电子接受能力较强的富勒烯衍生物.  相似文献   

4.
2-取代-5,5-二硝基嘧啶-4,6-二酮的合成和反应   总被引:1,自引:0,他引:1  
研究了2-取代嘧啶-4,6-二酮的硝化反应, 产物为2-取代-5,5-二硝基嘧啶-4,6-二酮(3), 收率>80%, 3与亲核试剂反应形成开环产物. 2-位取代基为烷基时, 嘧啶环5-位和侧链的α-位都发生反应, 当取代基为甲基时, 硝化产物为2-(二硝基亚甲基)-5,5-二硝基嘧啶-4,6-二酮(1), 1的水解产物为1,1-二氨基-2,2-硝基乙烯 (FOX-7) 和二硝基甲烷(2). 2-位取代基为羟基时, 硝化产物为5,5-二硝基巴比妥酸(7b), 7b水解可制得偕二硝基乙酰基脲(9b), 9b与KOH作用生成偕二硝基乙酰基脲钾盐(10b)和二硝基甲烷钾盐(11). 2-位取代基为氨基时, 硝化开环生成偕二硝基乙酰基胍(9a), 9a与KOH作用生成偕二硝基乙酰基胍钾盐(10a)和11. 当2-位无取代基时, 硝化产物无法分离, 结构推测为7c. 考察了亲核试剂对FOX-7收率的影响并对FOX-7的三种合成方法进行了评价, 对反应机理进行了探讨.  相似文献   

5.
贫电子环丙烷衍生物1以精制四氢呋喃为溶剂, 与2-巯基苯骈噻唑(2)封管加热反应, 得到产物34. 产物3经IR, MS, 1H NMR, 13C NMR和元素分析等数据确定其结构为: (R)-β-取代-(R)-γ-(2-巯基)苯骈噻唑基-γ-对位取代苯基丁酸或(S)-β-取代-(S)-γ-(2-巯基)苯骈噻唑基-γ-对位取代苯基丁酸(3); 产物4通过IR, MS, 1H NMR, 13C NMR, 2D-NOESY谱和元素分析等数据确定其结构为: 反式-β-取代-γ-对位取代苯基-3-丁烯酸(4). 对生成产物的机理也进行了推测.  相似文献   

6.
张靖  杨阳  魏忠  景旭  段春迎 《无机化学学报》2022,38(12):2469-2478
使用二茂铁构筑了2个新型金属有机大环:MCuMFe。2个大环化合物有效猝灭了有机染料的荧光,并可触发光致电子转移。较低的还原电位导致MCu在光催化质子还原和硝基还原2个反应中表现出更好的催化性能。底物的大尺寸导致硝基还原过程的效率降低。用Michaelis-Menten机理对光催化体系进行了验证,揭示了底物与催化剂之间相互作用的重要性。  相似文献   

7.
使用二茂铁构筑了2个新型金属有机大环: MCuMFe。2个大环化合物有效猝灭了有机染料的荧光,并可触发光致电子转移。较低的还原电位导致MCu在光催化质子还原和硝基还原2个反应中表现出更好的催化性能。底物的大尺寸导致硝基还原过程的效率降低。用Michaelis-Menten机理对光催化体系进行了验证,揭示了底物与催化剂之间相互作用的重要性。  相似文献   

8.
α-取代苯并噻吩乙炔及乙烯基为配体,与不同辅助配体键合的金属钌为氧化还原活性端基,分别合成并表征了α-取代苯并噻吩钌乙炔及钌乙烯配合物12,两个配合物均经X射线单晶衍射的确证。电化学性质表明配合物1具有较好的氧化还原可逆性,金属氧化态相对于2比较稳定。红外光谱电化学研究表明配合物12分别形成1+2+后,与金属相连的ν(C≡C)和ν(C≡O)伸缩振动吸收均发生变化,其中ν(C≡C)变化较大,可能由于形成了Ru=C=C结构;紫外可见近红外光谱电化学研究发现电解后,中性分子12在紫外区域的强吸收峰均逐渐降低,1+分别在可见及近红外580 nm,698 nm及874 nm处出现较弱的3个吸收峰,3个吸收峰可能归属于LMCT吸收。2+在296 nm处出现1个很弱的吸收峰,这不同于配合物1+,可能源于2+的稳定性。  相似文献   

9.
N′-(取代嘧啶-2-基)-N-菊酰硫脲的合成与生物活性研究   总被引:7,自引:0,他引:7  
采用活性基团拼接法, 将第一菊酸构型中的最高活性组分(+)-反式菊酸以及二氯菊酸引入到含取代嘧啶环的酰基硫脲结构中, 合成了5个未见文献报道的N′-(取代嘧啶-2-基)-N-(+)-反式菊酰硫脲衍生物(3a3e)和3个均未见文献报道的N′-(取代嘧啶-2-基)-N-二氯菊酰硫脲(3f3h), 结构经元素分析、IR和1H NMR得到确证. 初步的生物活性测试结果表明: 大部分化合物具有较好的杀菌活性, 有的化合物兼具除草和杀菌活性, 有的化合物兼具杀虫和杀菌活性.  相似文献   

10.
三联吡啶及其衍生物构筑的钴(Ⅱ)配合物构成了一大类钴(Ⅱ)自旋交叉家族化合物,然而目前报道的配合物大多由同种配体与钴(Ⅱ)离子组装形成。本文报道了3例由互补三联吡啶配体对定向组装的单核钴(Ⅱ)配合物的合成及自旋交叉性质,它们的固态自旋交叉行为可以通过三联吡啶4位的取代基有效调控。其中原型配合物1和三氟甲基取代的衍生物3在低温时为完全低自旋态(S=1/2),随着温度升高到400 K,部分铁(Ⅱ)离子的自旋态转变为S=3/2。氟取代衍生物表现出溶剂依赖的自旋转变行为,带有3个结晶水的配合物2晶体呈现与13类似的不完全自旋转变,然而在高温下完全脱除水分子的样品在260~340 K产生一个宽度约为50 K的热滞回线。有趣的是,配合物2晶格中的水分子的吸附和脱附在结构和磁性上均是可逆的。此外,吸收光谱和循环伏安测试表明配体上的取代基可以调控中心钴离子的电子结构。  相似文献   

11.
Reductive demetalation of manganese corroles: The substituent effect   总被引:1,自引:0,他引:1  
The reductive demetalation of manganese corroles was investigated in CH2Cl2/HCl (aqueous) solvent by using SnCl2 as reducing agent. It was found that the demetalation yields depend on the substituents of corrole macrocycle significantly. Electron- rich manganese corrole undergoes reductive demetalation more easily than electron-deficient ones. The isolated reductive demetalation yield of manganese 5,10,15-tris(phenyl)corrole in present system is moderate (46%). As for electron-deficient Mn(Ⅲ) 5,10,15-tris(pentafluorophenyl)corrole, the acid-induced demetalation in HOAc-HESO4 (V/V = 3:1) is preferable with an isolated yield of 67%.  相似文献   

12.
报道了3个2-(羟甲基)-N-甲基咪唑(Hhmmi)桥联的Mn2ⅡMn2Ⅲ四核配合物[Mn4(hmmi)6(DMF)2·(N3)2](ClO4)2(1),[Mn4(hmmi)6(H2O)2(N3)2](ClO4)2(2)和[Mn4(hmmi)6Cl4]·6CH3CN(3·6CH3CN)的合成、晶体结构和磁性. 在配合物1~3中,中心结构皆为四核蝶形混合价Mn结构,2个MnⅡ占据蝶形两翼位置,2个MnⅢ占据蝶形中间位置. MnⅢ离子间通过hmmi-上的μ3-烷氧原子桥联,相应MnⅢ-O-MnⅢ键角为101.3°~103.4°;而MnⅢ-MnⅡ离子间通过hmmi-上的μ3-和μ2-烷氧原子桥联,相应MnⅢ-O-MnⅡ键角为92.5°~113.7°. 对配合物1~3进行变温磁化率拟合,结果表明,MnⅢ-MnⅢ间呈铁磁相互作用,而MnⅢ-MnⅡ间以及Mn4分子间存在较弱的铁磁或反铁磁耦合.  相似文献   

13.
合成了两个中位苯基上具有甲氧基取代基的铜咔咯配合物(Tp-OCH3PC)Cu和(To,p-(OCH3)2PC)Cu,通过紫外-可见、红外光谱、元素分析、核磁共振及质谱对它们进行了表征。研究了配合物在非水溶剂中的电子顺磁共振、电化学和光谱电化学性质,结果表明无论在固体状态还是在非水溶剂中,配合物的中心金属离子均为三价铜Cu(Ⅲ),在给定的溶剂中Cu(Ⅲ)可以发生可逆的还原反应生成Cu(Ⅱ),也可以被可逆氧化为Cu(Ⅲ)的阳离子自由基。探讨了甲氧基取代基以及溶剂对配合物的紫外-可见光谱和氧化还原电位的影响。  相似文献   

14.
采用微量光度滴定法测定了两种具有不同取代基的新型咔咯化合物,三(4-氯苯基)咔咯(化合物1)和三(2,4-二氯苯基)咔咯(化合物2)在非水溶剂中的质子化和去质子化常数。结果表明:化合物1和化合物2在二氯甲烷中均可以与三氟乙酸反应得到一个质子生成正一价阳离子,其质子化常数(lgKb)分别为4.2和4.0。在甲醇溶液中,化合物1和化合物2与氢氧化钠反应时可以失去一个质子生成负一价阴离子,其去质子化常数(lgKa)分别为3.4和3.5。而在二氯甲烷中与碱反应时,化合物1和化合物2均能够一步失去两个质子生成负二价阴离子,其累积去质子化常数(lgβ2)分别为7.9和11.0。  相似文献   

15.
朱强  宫红  姜恒  王锐 《合成化学》2016,24(10):856-860
以过渡金属甲基磺酸盐[Mn(CH3SO3)2·2H2O, Cu(CH3SO3)2·4H2O, Co(CH3SO3)2·4H2O和Zn(CH3SO3)2·4H2O]为催化剂,在室温条件下催化醇的四氢吡喃化反应,并对反应条件进行了优化。结果表明:当醇用量为30 mmol,醇和3,4-二氢吡喃摩尔比为1.0 :1.1,甲基磺酸盐用量为1 mmol,二氯甲烷20 mL时,可高效催化醇的四氢吡喃化反应。与路易斯酸催化活性相比,过渡金属甲基磺酸盐催化醇的四氢吡喃化反应效果最好,催化酚的效果较差。用Mn(CH3SO3)2·2H2O和Cu(CH3SO3)2·4H2O催化正丁醇的四氢吡喃化反应,重复使用5次,收率分别为89%和92%。  相似文献   

16.
Treatment of the nido-1-CB8H12 (1) carborane with NaBH4 in THF at ambient temperature led to the isolation of the stable [arachno-5-CB8H13]- (2(-)), which was isolated as Na+[5-CB8H13]-.1.5 THF and PPh4 +[5-CB8H13]- in almost quantitative yield. Compound 2(-) underwent a boron-degradation reaction with concentrated hydrochloric acid to afford the arachno-4-CB7H13 (3) carborane in 70 % yield, whereas reaction between 2(-) and excess phenyl acetylene in refluxing THF gave the [closo-2-CB6H7]- (4-) in 66 % yield. Protonation of the Cs+4(-) salt with concentrated H2SO4 or CF3COOH in CH2Cl2 afforded a new, highly volatile 2-CB6H8 (4) carborane in 95 % yield, the deprotonation of which with Et3N in CH2Cl2 leads quantitatively to Et3NH+[2-CB6H7](-) (Et3NH+4(-)). Both compounds 4- and 4 can be deboronated through treatment with concentrated hydrochloric acid in CH2Cl2 to yield the carbahexaborane nido-2-CB5H9 (5) in 60 % yield. New compounds 2-, 3, and 4 were structurally characterised by the ab initio/GIAO/MP2/NMR method. The method gave superior results to those carried out using GIAO-HF when relating the calculated 11B NMR chemical shifts to experimental data.  相似文献   

17.
The solubility of gas-phase acetic acid (CH(3)COOH, HAc) and trifluoroacetic acid (CF(3)COOH, TFA) in aqueous sulfuric acid solutions was measured in a Knudsen cell reactor over ranges of temperature (207-245 K) and acid composition (40-75 wt %, H(2)SO(4)). For both HAc and TFA, the effective Henry's law coefficient, H*, is inversely dependent on temperature. Measured values of H* for TFA range from 1.7 × 10(3) M atm(-1) in 75.0 wt % H(2)SO(4) at 242.5 K to 3.6 × 10(8) M atm(-1) in 40.7 wt % H(2)SO(4) at 207.8 K. Measured values of H* for HAc range from 2.2 × 10(5) M atm(-1) in 57.8 wt % H(2)SO(4) at 245.0 K to 3.8 × 10(8) M atm(-1) in 74.4 wt % H(2)SO(4) at 219.6 K. The solubility of HAc increases with increasing H(2)SO(4) concentration and is higher in strong sulfuric acid than in water. In contrast, the solubility of TFA decreases with increasing sulfuric acid concentration. The equilibrium concentration of HAc in UT/LS aerosol particles is estimated from our measurements and is found to be up to several orders of magnitude higher than those determined for common alcohols and small carbonyl compounds. On the basis of our measured solubility, we determine that HAc in the upper troposphere undergoes aerosol partitioning, though the role of H(2)SO(4) aerosol particles as a sink for HAc in the upper troposphere and lower stratosphere will only be discernible under high atmospheric sulfate perturbations.  相似文献   

18.
Treatment of [Li(L1)]2 (1) or K(L2) (2) with SnX2 in Et2O yielded the heteroleptic beta-diketiminatotin(II) halides Sn(L1)Cl (3a), Sn(L1)Br (3b) or Sn(L2)Cl (4), even when an excess of the alkali metal beta-diketiminate was used [L1={N(R)C(Ph)}2CH, L2={N(R)C(Ph)CHC(But)N(R)}, R = SiMe3]. From and half an equivalent each of SnCl2.2H2O and SnCl2, or one equivalent of SnCl2.2H2O, the product was Sn(L3)Cl (5) or Sn(L4)Cl (6), in which one or both of the N-R bonds of L1 had been hydrolytically cleaved; the compound Sn(L5)Cl (7) was similarly obtained from and an equivalent portion of SnCl2.2H2O [L3={N(R)C(Ph)CHC(But)N(H)}, L4={N(H)C(Ph)CHC(But)N(H)} and L5={N(H)C(Ph)}2CH]. The halide exchange between 3a and 3b, studied by two-dimensional (119)Sn{1H}-NMR spectroscopy, is attributed to implicate a (mu-Cl)(mu-Br)-dimeric intermediate or transition state. The 13C{1H}-NMR spectra of or showed two distinct resonances for each group, which coalesced on heating, corresponding to DeltaG(338 K)= 69.4 (3a) or 72.8 (3b) kJ mol(-1). The chloride ligand of was readily displaced by treatment with NaNR2, CF3SO3H or CH2(COPh)2, yielding Sn(L1)X [X = NR2 (8), O3SCF3 (9) or {OC(Ph)}2CH (10)]. Oxidative addition of sulfur or selenium to gave the tin(IV) terminal chalcogenides Sn(E)(L1)(NR2)[E = S (11) or Se (12)]. The X-ray structures of the cocrystal of 3a/3b and of the crystalline compounds 5, 6, 8, 11 and are presented, as well as multinuclear NMR spectra of each of the new compounds.  相似文献   

19.
锰(Ⅲ)Corrole配合物催化DNA氧化断裂   总被引:2,自引:0,他引:2  
报道了这类单羟基Corrole锰(Ⅲ)配合物对DNA的催化氧化断裂作用.  相似文献   

20.
Reaction of TiCl(4) or ZrI(4) with the soft, neutral o-C(6)H(4)(CH(2)EMe)(2) (E = S or Se) in anhydrous CH(2)Cl(2) (or toluene) yields the distorted octahedral chelate complexes [MX(4){o-C(6)H(4)(CH(2)EMe)(2)}]. Using Et(2)Se gives [MX(4)(Et(2)Se)(2)] (M = Zr, X = Cl or I; M = Hf, X = I). The Sn(IV) analogues, [SnCl(4){o-C(6)H(4)(CH(2)EMe)(2)}] and [SnCl(4)(Et(2)Se)(2)] were obtained similarly. These complexes have been characterised spectroscopically and analytically, and crystal structures of trans-[SnCl(4)(Et(2)Se)(2)] and some selenonium salts derived as minor by-products from the parent Group 4 complexes are described. The neutral chalcogenoether complexes have been evaluated as single source precursors to ME(2)/ME thin films via LPCVD. [TiCl(4){o-C(6)H(4)(CH(2)EMe)(2)}] leads to the deposition of air and moisture stable TiE(2) films (with no residual Cl). Coverage of the substrate is uniform with platelet growth perpendicular to the surface. The heavier Zr(IV) species do not lead to significant ZrE(2) deposition. On the other hand, LPCVD of [SnCl(4){o-C(6)H(4)(CH(2)SMe)(2)}] leads to deposition of SnS(2) at lower temperatures and SnS at higher temperatures, while [SnCl(4){o-C(6)H(4)(CH(2)SeMe)(2)}] gives rather uneven coatings of SnSe(2). The Et(2)Se derivative, [SnCl(4)(Et(2)Se)(2)] leads to uniform deposition of SnSe(2) with growth perpendicular to the substrate surface. The SnE(2)/SnE films are stable indefinitely to air and moisture. The generation of TiS(2), SnS(2) and SnS in this way are very rare examples of metal sulfide deposition from C-S bond fission within a thioether complex.  相似文献   

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