titanium(III) citrate

• 分子结构分类: 有机化合物 - 有机酸及其衍生物 - 羧酸及其衍生物
• 英文名称: titanium(III) citrate
• 英文别名: titanium citrate；Ti(III) citrate；Ti(III)-citrate；2-Hydroxypropane-1,2,3-tricarboxylate;titanium(3+)
• 化学式: C₆H₅O₇*Ti
• 分子量: 236.981
• InChiKey: DDUPILAANWASPJ-UHFFFAOYSA-K

计算性质

• 辛醇/水分配系数(LogP)：
  -5.26
• 重原子数：
  14
• 可旋转键数：
  2
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.5
• 拓扑面积：
  141
• 氢给体数：
  1
• 氢受体数：
  7

反应信息

• 作为反应物：
  描述：

  niobium oxalate 、 titanium(III) citrate 、 氧气 、 copper(II) nitrate 、 samarium(III) nitrate 以 水 、 乙二胺 为溶剂， 生成
  参考文献：
  名称：

  Synthesis and Magnetic Properties of New Pyrochlore Compounds Sm1.6M0.4Ti1.6Nb0.4O7 (M = Cu, Ni)

  摘要：

  New pyrochlore compounds Sm1.6M0.4Ti1.6Nb0.4O7 (M = Cu, Ni) are synthesized by a wet chemical method. The crystal structure of the compounds belongs to a cubic system with a cubic face-centered cell. The temperature dependence of the inverse susceptibility of Sm11.6M0.4Ti1.6Nb0.4O7 (M = Cu, Ni) in the paramagnetic region shows the ferrimagnetic behavior of the compounds. Fitting to the experimental plot of the inverse susceptibility of the compound versus temperature was performed. The temperature at 1/chi = 0 (T-FN) is (150 +/- 5) K for Sn11.6Cu0.4Ti1.6Nb0.4O7 and (164 +/- 5) K for Sm1.6Ni0.4Ti1.6Nb0.4O7. The compounds are weak ferrimagnets, not spin glasses.

  DOI：

  10.1002/1521-396x(200211)194:1<331::aid-pssa331>3.0.co;2-4
• 作为产物：
  描述：

  titanium(III) chloride 、 sodium citrate 以 水 为溶剂， 生成 titanium(III) citrate
  参考文献：
  名称：

  镍取代的天青蛋白中氧化还原活性的电化学，光谱和密度泛函理论表征：乙酰辅酶A合酶模型

  摘要：

  含镍的酶是全球氢，二氧化碳和甲烷循环的关键参与者。这些酶中的许多酶都依赖于关键催化中间体中的Ni I氧化态。但是，由于这些物种的高反应性，通常难以将其分离到金属酶中。在本报告中，我们描述并描述了在电子转移蛋白天青素内已产生的模型生物学Ni I物种。已显示用镍代替天然铜辅因子可保持蛋白质的氧化还原活性。与NHE相比，在-590 mV处观察到Ni II / I对，界面电子转移速率为70 s –1。Ni II的化学还原Az生成稳定的物质，在350 nm处具有很强的吸收特性，并且具有主要g值为2.56和2.10的高度各向异性的轴向EPR信号。密度泛函理论计算提供了对Ni I物种的电子和几何结构的洞察力，暗示了三角形的平面配位环境。该低配位镍位点的预测光谱特征与实验数据非常吻合。分子轨道分析表明，以金属为中心和以配体为中心的反应性都有潜力，突出了金属硫醇键的共价性。稳定的Ni I的表征 模型蛋白中的

  DOI：

  10.1021/acs.inorgchem.5b01103
• 作为试剂：
  描述：

  2-溴甲基萘 在 vitamin B12 titanium(III) citrate 、 Tris buffer 、 四丁基氢氧化铵 作用下， 以 水 、 乙腈 为溶剂， 反应 1.0h， 以79%的产率得到2-(2-萘-2-基乙基)萘
  参考文献：
  名称：

  新的维生素B（12）催化的碳[键]碳键形成反应，芳基烯烃的还原二聚化的机理研究。

  摘要：

  在催化性维生素B（12）和还原剂（例如柠檬酸Ti（III）或Zn）存在下，芳基烯烃以不寻常的区域选择性二聚，从而在每个偶联配偶体的苄基碳之间形成碳键碳键。对于单-和1，1-二取代的烯烃，以良好至优异的产率获得二聚产物。含有一种芳基烯烃的二烯以良好的产率进行分子内环化。但是，1,2-二取代和三取代的烯烃是不反应的。使用自由基阱的机理研究表明，苄基自由基的参与，并且产物分布中非对映选择性的缺乏与两种这样的反应性中间体的二聚化相一致。反应需要强还原剂，并起着两个作用。它使反应后生成的催化剂的Co（II）形式返回到活性Co（I）状态，并且通过除去Co（II），还可以防止烷基自由基与Cob（II）阿拉明的非生产性重组。由芳基烯烃和Cob（I）阿拉明形成苄基的机理提出了一个有趣的问题。单电子转移探针的结果表明自由基的产生不太可能涉及电子转移。讨论了几种替代机制。单电子转移探针的结果表明自由基的产生不太

  DOI：

  10.1021/jo0160470

文献信息

• Electrochemical, Spectroscopic, and Density Functional Theory Characterization of Redox Activity in Nickel-Substituted Azurin: A Model for Acetyl-CoA Synthase
  作者：Anastasia C. Manesis、Hannah S. Shafaat

  DOI：10.1021/acs.inorgchem.5b01103

  日期：2015.8.17

  in critical catalytic intermediates. However, due to the highly reactive nature of these species, their isolation within metalloenzymes has often proved elusive. In this report, we describe and characterize a model biological NiI species that has been generated within the electron transfer protein, azurin. Replacement of the native copper cofactor with nickel is shown to preserve the redox activity of

  含镍的酶是全球氢，二氧化碳和甲烷循环的关键参与者。这些酶中的许多酶都依赖于关键催化中间体中的Ni I氧化态。但是，由于这些物种的高反应性，通常难以将其分离到金属酶中。在本报告中，我们描述并描述了在电子转移蛋白天青素内已产生的模型生物学Ni I物种。已显示用镍代替天然铜辅因子可保持蛋白质的氧化还原活性。与NHE相比，在-590 mV处观察到Ni II / I对，界面电子转移速率为70 s –1。Ni II的化学还原Az生成稳定的物质，在350 nm处具有很强的吸收特性，并且具有主要g值为2.56和2.10的高度各向异性的轴向EPR信号。密度泛函理论计算提供了对Ni I物种的电子和几何结构的洞察力，暗示了三角形的平面配位环境。该低配位镍位点的预测光谱特征与实验数据非常吻合。分子轨道分析表明，以金属为中心和以配体为中心的反应性都有潜力，突出了金属硫醇键的共价性。稳定的Ni I的表征 模型蛋白中的
• Enhancement of Ce/Cr Codopant Solubility and Chemical Homogeneity in TiO₂ Nanoparticles through Sol–Gel versus Pechini Syntheses
  作者：Wen-Fan Chen、Sajjad S. Mofarah、Dorian Amir Henry Hanaor、Pramod Koshy、Hsin-Kai Chen、Yue Jiang、Charles Christopher Sorrell

  DOI：10.1021/acs.inorgchem.8b00926

  日期：2018.6.18

  Ce/Cr codoped TiO2 nanoparticles were synthesized using sol-gel and Pechini methods with heat treatment at 400 degrees C for 4 h. A conventional sol-gel process produced well-crystallized anatase, while Pechini synthesis yielded less-ordered mixed-phase anatase + rutile; this suggests that the latter method enhances Ce solubility and increases chemical homogeneity but destabilizes the TiO2 lattice. Greater structural disruption from the decomposition of the Pechini precursor formed more open agglomerated morphologies, while the lower levels of structural disruption from pyrolysis of the dried sol-gel precursor resulted in denser agglomerates of lower surface areas. Codoping and associated destabilization of the lattice reduced the binding energies in both powders. Cr4+ formation in sol-gel powders and Cr6+ formation in Pechini powders suggest that these valence changes derive from synergistic electron exchange from intervalence and/or multivalence charge transfer. Since Ce is too large to allow either substitutional or interstitial solid solubility, the concept of integrated solubility is introduced, in which the Ti site and an adjacent interstice are occupied by the large Ce ion. The photocatalytic performance data show that codoping was detrimental owing to the effects of reduced crystallinity from lattice destabilization and surface area. Two regimes of mechanistic behavior are seen, which are attributed to the unsaturated solid solutions at lower codopant levels and supersaturated solid solutions at higher levels. The present work demonstrates that the Pechini method offers a processing technique that is superior to sol-gel because the former facilitates solid solubility and consequent chemical homogeneity.
• Reduction of Flavodoxin by Electron Bifurcation and Sodium Ion-dependent Reoxidation by NAD+ Catalyzed by Ferredoxin-NAD+ Reductase (Rnf)
  作者：Nilanjan Pal Chowdhury、Katharina Klomann、Andreas Seubert、Wolfgang Buckel

  DOI：10.1074/jbc.m116.726299

  日期：2016.6

  Electron-transferring flavoprotein (Etf) and butyryl-CoA dehydrogenase (Bcd) from Acidaminococcus fermentans catalyze the endergonic reduction of ferredoxin by NADH, which is also driven by the concomitant reduction of crotonyl-CoA by NADH, a process called electron bifurcation. Here we show that recombinant flavodoxin from A. fermentans produced in Escherichia coli can replace ferredoxin with almost equal efficiency. After complete reduction of the yellow quinone to the blue semiquinone, a second 1.4 times faster electron transfer affords the colorless hydroquinone. Mediated by a hydrogenase, protons reoxidize the fully reduced flavodoxin or ferredoxin to the semi-reduced species. In this hydrogen-generating system, both electron carriers act catalytically with apparent K-m = 0.26 mu M ferredoxin or 0.42 mu M flavodoxin. Membrane preparations of A. fermentans contain a highly active ferredoxin/flavodoxin-NAD(+) reductase (Rnf) that catalyzes the irreversible reduction of flavodoxin by NADH to the blue semiquinone. Using flavodoxin hydroquinone or reduced ferredoxin obtained by electron bifurcation, Rnf can be measured in the forward direction, whereby one NADH is recycled, resulting in the simple equation: crotonyl-CoA + NADH + H+ = butyryl-CoA + NAD(+) with K-m = 1.4 mu M ferredoxin or 2.0 mu M flavodoxin. This reaction requires Na+ (K-m = 0.12 mM) or Li+ (K-m = 0.25 mM) for activity, indicating that Rnf acts as a Na+ pump. The redox potential of the quinone/semiquinone couple of flavodoxin (Fld) is much higher than that of the semiquinone/hydroquinone couple. With free riboflavin, the opposite is the case. Based on this behavior, we refine our previous mechanism of electron bifurcation.
• Synthesis and Magnetic Properties of New Pyrochlore Compounds Sm1.6M0.4Ti1.6Nb0.4O7 (M = Cu, Ni)
  作者：X.L. Li、Y. Ma、H. Xiong、Y.Q. Jia、X.H. Zhao、S.K. Ruan、J. Du

  DOI：10.1002/1521-396x(200211)194:1<331::aid-pssa331>3.0.co;2-4

  日期：2002.11

  New pyrochlore compounds Sm1.6M0.4Ti1.6Nb0.4O7 (M = Cu, Ni) are synthesized by a wet chemical method. The crystal structure of the compounds belongs to a cubic system with a cubic face-centered cell. The temperature dependence of the inverse susceptibility of Sm11.6M0.4Ti1.6Nb0.4O7 (M = Cu, Ni) in the paramagnetic region shows the ferrimagnetic behavior of the compounds. Fitting to the experimental plot of the inverse susceptibility of the compound versus temperature was performed. The temperature at 1/chi = 0 (T-FN) is (150 +/- 5) K for Sn11.6Cu0.4Ti1.6Nb0.4O7 and (164 +/- 5) K for Sm1.6Ni0.4Ti1.6Nb0.4O7. The compounds are weak ferrimagnets, not spin glasses.