106967-33-3Relevant academic research and scientific papers
Luminescent Carbazole-Based EuIII and YbIII Complexes with a High Two-Photon Absorption Cross-Section Enable Viscosity Sensing in the Visible and near IR with One- And Two-Photon Excitation
De Bettencourt-Dias, Ana,Fetto, Natalie R.,Monteiro, Jorge H. S. K.,Tucker, Matthew J.
, p. 3193 - 3199 (2020)
The newly synthesized EuIII and YbIII complexes with the new carbazole-based ligands CPAD2- and CPAP4- display the characteristic long-lived metal-centered emission upon one- and two-photon excitation. The EuIII complexes show the expected narrow emission bands in the red region, with emission lifetimes between 0.382 and 1.464 ms and quantum yields between 2.7% and 35.8%, while the YbIII complexes show the expected emission in the NIR region, with emission lifetimes between 0.52 and 37.86 μs and quantum yields between 0.028% and 1.12%. Two-photon absorption cross sections (σ2PA) as high as 857 GM were measured for the two ligands. The complexes showed a strong dependence of the one- and two-photon sensitized emission intensity on solvent viscosity in the range of 0.5-200 cP in the visible and NIR region.
Synthesis and Hydrolysis of 4-Chloro-PyMTA and 4-Iodo-PyMTA Esters and Their Oxidative Degradation with Cu(I/II) and Oxygen
Qi, Mian,Hülsmann, Miriam,Godt, Adelheid
supporting information, p. 3773 - 3784 (2016/10/30)
We disclose the syntheses of ethyl and tert-butyl esters of 4-chloro-PyMTA and 4-iodo-PyMTA from the commercially available chelidamic acid monohydrate in 39-67% overall yield. Additionally, ester hydrolyses with aqueous NaOH (ethyl esters) or trifluoroacetic acid (tert-butyl esters) are reported. The resulting materials contain 4-halo-PyMTA in mixture with partially deprotonated or partially protonated 4-halo-PyMTA. The ligand content expressed as the content of the common structural motifs of the present species, namely [PyMTA - 4 H+4- (basic hydrolysis) and PyMTA (acidic hydrolysis), was determined to be 90-94 wt % by1H NMR spectroscopy using maleic acid as an internal standard. The tert-butyl esters were easily hydrolyzed with aqueous alkali hydroxide, with a decreasing rate in the series NaOH, KOH, LiOH. This finding indicates a Lewis acid assisted ester cleavage with the Na+ ion fitting best to the multidentate ligand. Unexpectedly, PyMTA esters are incompatible with Cu(I/II) salts in the presence of oxygen. Under these conditions, one of the two aminomethyl groups is converted into a formyl group. This reaction not only limits the application of Cu(I/II)-catalyzed reactions but also necessitates trapping of any copper ions (e.g., with a metal ion scavenger) before the material is exposed to oxygen.
NOVEL LUMINESCENT LANTHANIDE CHELATES WITH ENHANCED EXCITATION PROPERTIES
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Paragraph 0093; 0094, (2013/07/25)
The present application discloses a luminescent lanthanide chelate comprising one or more chromophoric moieties of the formula (I) or of the formula (III) wherein R1, R2 and R2* each independently are selected from carbon-containing substituents forming a C—O bond with the neighbouring oxygen atom, R3 and R4 each represent a bond between the chromophoric moiety and other moieties of the chelate, and Ln3+ is a lanthanide ion, as well as the corresponding luminescence lanthanide chelating ligand. The application also discloses a detectable molecule comprising a biospecific binding reactant (such as an antibody) conjugated to the luminescent lanthanide chelate as well as a method of carrying out a biospecific binding assay, the use of such a detectable molecule in a specific bioaffinity based binding assay utilizing time-resolved fluorometric determination of a specific luminescence, and a solid support material conjugated with the luminescent lanthanide chelate.
Synthesis of 4-(Phenylethynyl)-2,6-bispyridine
Takalo, Harri,Pasanen, Paavo,Kankare, Jouko
, p. 373 - 377 (2007/10/02)
The synthesis of 4-(phenylethynyl)-2,6-bispyridine is described.Two separate routes were investigated to reach the key intermediate 4-bromo-2,6-bis(bromomethyl)pyridine.
