18226-42-1Relevant articles and documents
Palladium nanoparticles-decorated graphene nanosheets as highly regioselective catalyst for cyclotrimerization reaction
Cheng, Jinsheng,Tang, Longhua,Li, Jinghong
, p. 5159 - 5168 (2011)
Novel palladium nanoparticles/graphene-based composites were prepared by a method involving palladium nanoparticles in situ growth on chitosan- functionalized graphene. The resulted composites showed uniform palladium nanoparticles distribution, which were characterized by Fourier transform infrared spectrometry (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy, atomic force microscopy (AFM), X-ray diffraction spectroscopy (XRD) and electron diffraction pattern (ED), etc. Moreover, such graphene-based nanocomposites were successfully applied to catalyze the cyclotrimerization of acetylene with high regioselectivity (=99.5%) and superior recycling performance without the assistance of any ligands. Copyright
Octupolar organometallic Pt(II) NCN-pincer complexes; Synthesis, electronic, photophysical, and NLO properties
Batema, Guido D.,van Walree, Cornelis A.,van Klink, Gerard P.M.,de Mello Donegá, Celso,Meijerink, Andries,Perez-Moreno, Javier,Clays, Koen,van Koten, Gerard
, p. 246 - 252 (2018)
A series of organometallic octupolar 1,3,5-substituted-2,4,6-styryl-benzene complexes was synthesized by post-modification of parent [PtCl(NCN-CHO-4)], i.e. 1,3,5-tri-R-2,4,6-tris[(4-(PtCl)(3,5-bis[(dimethylamino)methyl]styryl)]benzene (NCN = [C6H2(CH2NMe2)2-2,6]– in which R = OMe, H, Br (1–3). Their synthesis involved a triple Horner-Wadsworth-Emmons reaction of [PtCl(NCN-CHO-4)] with the appropriate tris[(diethoxyphosphoryl)]methyl]benzene derivative. The 195Pt{1H} NMR chemical shift reflects the electronic properties of the π-system to which it is connected. The UV/Vis bands of the octupolar platinum complexes are only slightly red-shifted (by 5–12 nm) with respect to those of corresponding stilbenoid Pt-Cl pincer compounds (i.e., the separate branches), suggesting that there is only a limited electronic interaction between these branches. The fluorescence Stokes shift, quantum yields and lifetimes of 1–3 also are of the same order of magnitude as those of stilbenoid Pt-Cl pincer compounds, indicating that a dipolar excited state is formed, which is localized on one of the three branches. The hyper-Rayleigh scattering technique revealed hyperpolarizabilites βHRS of 430, 870 and 183 × 10?30 esu for 1, 2 and 3, respectively, which are among the highest for transition metal complexes. The highest value was found for the compound lacking a donor or acceptor group at the central core, lending support to the idea that dispersion overwhelms charge transfer in determining the magnitude of the first hyperpolarizability in octupolar compounds.
Control of the optical properties of a star copolymer with a hyperbranched conjugated polymer core and poly(ethylene glycol) arms by self-assembly
Qiu, Feng,Tu, Chunlai,Chen, Yan,Shi, Yunfeng,Song, Liang,Wang, Ruibing,Zhu, Xinyuan,Zhu, Bangshang,Yan, Deyue,Han, Tao
, p. 12710 - 12717 (2010)
A self-assembly approach to tuning the optical properties of a star copolymer is reported herein. The star copolymer HCP-star-PEG with a hyperbranched conjugated polymer (HCP) core and many linear poly(ethylene glycol) (PEG) arms has been prepared successfully. The HCP core was synthesized by Wittig coupling of N-(n-hexyl)-3,6-diformylcarbazole and 1,3,5- bis[(triphenylphosphonio)methyl]benzene tribromide. Subsequently, the linear PEG arms were grafted onto the HCP core by acylhydrazone connection. It was found that the optical properties of HCP-star-PEG in chloroform solution changed on addition of acid. Both 1H NMR and UV/Vis spectroscopic investigations confirmed that the variation of the optical properties was related to the complexation of the acid and the imine bond in the acylhydrazone group. HCP-star-PEG self-assembled into core-shell micelles in the mixed solvent of chloroform and acetonitrile, which affected the protonation of the imine bond. Therefore the optical properties of HCP-star-PEG can be readily controlled by self-assembly. Tuning a star copolymer: A star copolymer (HCP-star-PEG) with a hyperbranched conjugated (HCP) core and many poly(ethylene glycol) (PEG) arms has been synthesized through an acylhydrazone connection. The optical properties of HCP-star-PEG changed on complexation of acid (see figure). With different proportions of chloroform and acetonitrile, the optical properties of HCP-star-PEG can be easily controlled by self-assembly of the star polymer.
Synthesis of tris(β-diketones) and study of their complexation with some transition metals
Podyachev,Sudakova,Galiev,Mustafina,Syakaev,Shagidullin,Bauer,Konovalov
, p. 2000 - 2007 (2006)
New chelating ligands consisting of three β-diketone fragments, viz., 1,3,5-tris[(acetylaceton-3-yl)methyl]benzene, 1,3,5-tris[(benzoylaceton-3-yl) methyl]benzene, and 1,3,5-tris[(dibenzoylmethan-1-yl)methyl]benzene, linked to each other through the mesit
Synthesis and analysis of in vitro anti-arthritic activity of dendrimers with methyl, ethyl and isopropyl salicylates as surface groups
Jayanthi, Mani,Rajakumar, Perumal
, p. 63208 - 63215 (2014)
Frchet type dendrimers with salicylates as surface groups have been synthesized using the divergent approach and their in vitro anti-arthritic activity was analyzed by inhibition of protein denaturation.
Synthesis of bis- and tris(indolinylidenemethyl)benzenes by one-pot reactions of polylithiated nitriles with bis(imidoyl)chlorides of oxalic acid
Langer, Peter,Anders, Joachim T.
, p. 686 - 691 (2002)
The reaction of polylithiated di- and tricyanomethylbenzenes with oxalic acid-bis(imidoyl)chlorides afforded novel oligo(indolinylidenemethyl)benzenes with the formation of up to six carbon-carbon bonds. The UV/Vis spectroscopic features of these and related compounds were studied. 1,4-Disubstituted benzenes containing a large π-system have been efficiently prepared by the reaction of dianions with 1,4-dicyanobenzene. Wiley-VCH Verlag GmbH, 69451 Weinheim, Germany, 2002.
Aromatic Linkers Unleash the Antiproliferative Potential of 3-Chloropiperidines Against Pancreatic Cancer Cells
Helbing, Tim,Carraro, Caterina,Francke, Alexander,Sosic, Alice,De Franco, Michele,Gandin, Valentina,G?ttlich, Richard,Gatto, Barbara
supporting information, p. 2040 - 2051 (2020/09/21)
In this study, we describe the synthesis and biological evaluation of a set of bis-3-chloropiperidines (B?CePs) containing rigid aromatic linker structures. A modification of the synthetic strategy also enabled the synthesis of a pilot tris-3-chloropiperidine (Tri-CeP) bearing three reactive meta-chloropiperidine moieties on the aromatic scaffold. A structure–reactivity relationship analysis of B?CePs suggests that the arrangement of the reactive units affects the DNA alkylating activity, while also revealing correlations between the electron density of the aromatic system and the reactivity with biologically relevant nucleophiles, both on isolated DNA and in cancer cells. Interestingly, all aromatic 3-chloropiperidines exhibited a marked cytotoxicity and tropism for 2D and 3D cultures of pancreatic cancer cells. Therefore, the new aromatic 3-chloropiperidines appear to be promising contenders for further development of mustard-based anticancer agents aimed at pancreatic cancers.
Dendritic architectures by orthogonal thiol-maleimide "click" and furan-maleimide dynamic covalent chemistries
Frayne, Stephen H.,Stolz, Robert M.,Northrop, Brian H.
supporting information, p. 7878 - 7883 (2019/09/06)
A set of dendrons and dendrimers is synthesized divergently using an orthogonal combination of kinetically-driven thiol-maleimide "click" chemistry and thermodynamically reversible furan-maleimide cycloaddition/retrocycloaddition reactions. Growth is controlled by taking advantage of the selective thiol-ene addition of thiols to the electron withdrawn alkene of maleimide in the presence of electron rich alkene of oxanorbornene. Subsequent activation of growing dendrons/dendrimers requires only heat to induce the dynamic covalent liberation of peripheral furan protecting groups. The methodology introduced provides a new route to multifunctional dendrimers that could, in principle, be synthesized by introducing different branched monomers at any stage of dendrimer growth, allowing dendrimer architectures and properties to be better tailored to their intended applications.
