Salen配体和中离子卡宾(MIC)配体在均相催化中构成重要的配体类别。在本文中,我们描述了Salen部分和MIC供体在同一催化剂实体中的首次整合。可以通过首先在N 2 O 2塞伦球中安装一个金属中心(Ni(II),Pd(II)),然后将金属离子碳烯(Ag(I),Pd)金属化,来选择性地制备同金属和杂金属多核金属配合物(II))。银络合物可用于金属转移以形成Au(III)络合物。几种配合物在将吲哚的1,4-加成至硝基烯烃中显示出催化活性。
Salen配体和中离子卡宾(MIC)配体在均相催化中构成重要的配体类别。在本文中,我们描述了Salen部分和MIC供体在同一催化剂实体中的首次整合。可以通过首先在N 2 O 2塞伦球中安装一个金属中心(Ni(II),Pd(II)),然后将金属离子碳烯(Ag(I),Pd)金属化,来选择性地制备同金属和杂金属多核金属配合物(II))。银络合物可用于金属转移以形成Au(III)络合物。几种配合物在将吲哚的1,4-加成至硝基烯烃中显示出催化活性。
artificial catalysts for asymmetric synthesis. Polyfunctional catalysts are considered to be a promising tool for achieving excellent catalytic efficiency. A polyfunctional catalyst system was developed, which incorporates two Lewisacidic/Brønsted basic cobalt centers in combination with triazolium moieties that are crucial for high reactivity and excellent stereoselectivity in the direct1,4‐addition of
Phenylene-Diimine-Capped Conjugate of Lower Rim 1,3-Calix[4]Arene As Molecular Receptor for Mg<sup>2+</sup> via Arm Conformational Changes Followed by Aggregation and Mimicking the Species by Molecular Mechanics
of Mg2+ in the complex. The L binds Mg2+ octahedrally using the tetradentate L2– and two additional acetic acid moieties by bringing conformational changes as studied on the basis of MM computations. The conformational changes that occur in the capped arms upon Mg2+ binding were supported experimentally by NOESY. AFM and SEM studies showed that spherical particles of L are modified into flower and
Triazole-Linked-Thiophene Conjugate of Calix[4]arene: Its Selective Recognition of Zn<sup>2+</sup> and as Biomimetic Model in Supporting the Events of the Metal Detoxification and Oxidative Stress Involving Metallothionein
of the coordinated zinc from its Cys/DTT complex by heavy metal ion (viz. Cd2+ and Hg2+), as in the metal detoxification process or by ROS (such as H2O2) as in the oxidative stress, has been well demonstrated using the conjugate L through the fluorescence intensity retrieval wherein the fluorescence intensity is the same as that observed with [ZnL], which in turn mimics the zinc sensing element (MTF)
超分子杯[4]芳烃共轭物(L)已开发成为一种灵敏的选择性传感器,通过使用荧光,吸收和ESI MS以及可视荧光颜色,对12种金属离子中HEPES缓冲液中的Zn 2+进行了检测。使用从头算密度函数理论(DFT)与时变密度函数理论(TDDFT)结合的研究,证明了杯[4]亚芳基共轭物L及其锌配合物[Zn L ]的结构,电子和发射性质计算。TDDFT计算表明,L荧光行为的转换主要是由于锌利用了亚胺部分的孤对电子2+。通过从[Zn L ]中去除Zn 2+并形成等效的Cys / DTT·Zn}加合物,所得的荧光配合物[Zn L ]已用作检测含-SH分子的辅助传感化学集合。存在于金属硫蛋白中的那些。在金属解毒过程中,通过重金属离子(即Cd 2+和Hg 2+)置换,然后通过ROS(例如H 2 O 2)置换其Cys / DTT络合物中的配位锌。在氧化应激中,已经使用结合物L很好地证明了这一点。通过荧光强度检索,其中荧光强度与用[Zn
Imino–Phenolic–Pyridyl Conjugates of Calix[4]arene (L<sub>1</sub> and L<sub>2</sub>) as Primary Fluorescence <i>Switch-on</i> Sensors for Zn<sup>2+</sup> in Solution and in HeLa Cells and the Recognition of Pyrophosphate and ATP by [ZnL<sub>2</sub>]
triazole-linked calix[4]areneconjugates, viz. L1 and L2, were synthesized and characterized. These two conjugates were shown to be selective and sensitive for Zn2+ among the 12 metal ions studied in HEPES buffer medium by fluorescence, absorption, and visual color change with the detection limit of ∼31 and ∼112 ppb, respectively, by L1 and L2. Moreover, the utility of the conjugates L1 and L2 in showing
基于吡啶基的三唑连接的杯[4]芳烃偶联物,即。合成并表征了L 1和L 2。在HEPES缓冲液中研究的12种金属离子中,通过荧光,吸收和肉眼观察到的颜色变化,这两种结合物对Zn 2+具有选择性和敏感性,L 1的检出限分别为〜31和〜112 ppb。和L 2。此外,使用HeLa细胞通过荧光成像监测,也已经证明了缀合物L 1和L 2在活细胞中显示锌识别的效用。L的锌络合物分离出1和L 2,并通过单晶XRD确定了[Zn L 1 ]的结构,并通过DFT计算确定了[Zn L 2 ]的结构。进行TDDFT计算是为了证明受体及其锌络合物的电子性质。分离的锌络合物,即。[Zn L 1 ]和[Zn L 2 ]已被用作用于识别阴离子的分子工具,基于它们对Zn 2+的结合亲和力。[Zn L 2]被发现对其他含18个阴离子敏感且对含磷酸盐的离子和分子具有选择性,特别是对焦磷酸盐(PPi)和ATP敏感;但是,[Zn L
A 1,3-Capped Calix[4] Conjugate Possessing an Amine Moiety as an Anion Receptor: Reversible Anion Sensing Detected by Spectroscopy and Characterization of the Supramolecular Features by Microscopy
作者:Anita Nehra、Deepthi S. Yarramala、Chebrolu Pulla Rao
DOI:10.1002/chem.201600609
日期:2016.6.20
A phenylenediamine‐capped conjugate of calix[4]arene (Lamino) was synthesized by reducing its precursor, Limino, with sodium borohydride in methanol. The Lamino sample binds to anions due to the more flexible and bent conformation of the capped aminophenolic binding core, compared to the precursor Limino. The Lamino sample showed selectivity towards H2PO4− by exhibiting a ratiometric increase in emission
通过在甲醇中用硼氢化钠还原其前体L亚氨基来合成杯芳烃[4]亚芳基(L氨基)的苯二胺封端的共轭物。的大号氨基样品结合于阴离子由于封端的氨基酚的结合核心的更加灵活和弯曲构,相比于前体大号亚氨基。的大号氨基样品显示选择性朝ħ 2 PO 4 -与(1.2±0.2)μ的检测极限通过显示出约在发射一个比例增加11倍米的研究((116±20)ppb)的超过15周的阴离子,包括其他磷酸盐,例如P 2O 7 4-,腺苷一磷酸(AMP 2-),腺苷二磷酸(ADP 2-)和腺苷三磷酸(ATP 2-)。的大号氨基样本示出了在增加的吸光度λ在H的存在= 315纳米2 PO 4 -,CO 3 2-,HCO 3 -,CH 3 CO 2 - ,和F - 。的1的1 H NMR光谱滴定大号氨基用H 2 PO 4 -,F-和CH 3 CO 2 -显示,在亚苯基封端的和水杨部分大的变化,并且由此,证实了氨基酚区域作为结合核心。然而,这些阴离子的结合强度遵循趋势ħ