6165-68-0Relevant articles and documents
Mechano- and Thermo-responsive Luminescence of Crystalline Thienylbenzothiadiazole Derivatives: Stepwise Hypsochromic Switching of Near-Infrared Emission
Ito, Suguru,Tachikawa, Takashi,Yoshida, Ryohei
, p. 547 - 558 (2022/01/03)
Organic crystals that exhibit mechanochromic luminescence (MCL) switch their emission colors in response to mechanical stimuli, and the original emission colors usually recover upon heating the mechanically changed state. Contrary to the recent enthusiastic investigations of MCL crystals, only a limited number of organic crystals transform to another state showing a third emission color upon sequential exposure to mechanical and thermal stimuli. The development of near-infrared (NIR) emissive organic crystals is another challenge. Although several NIR-emissive crystals that can respond to mechanical stimuli have been developed, further investigations are still required for the multi-stimuli-responsive emission involving the NIR region. In this study, we investigate the mechano-responsive properties of crystalline thienylbenzothiadiazole derivatives. The maximum emission wavelengths of these crystals are observed between blue-green to NIR (502–731 nm), which depend on the substituents R1 and R2 on the thiophene and benzothiadiazole rings, respectively. All derivatives shift the emission wavelength in the hypsochromic direction upon grinding. Moreover, derivatives having a carbonyl group on R2 display further hypsochromic shifts of their emission bands by thermal annealing of the ground states. Specifically, a stepwise hypsochromic shift of the emission from the NIR region has been achieved for a derivative bearing phenyl and formyl groups (R1 = Ph, R2 = CHO). Powder X-ray diffraction analysis, differential scanning calorimetry, and spatially resolved fluorescence microscopy have suggested that the stepwise emission-color switching should be attributed to the crystal-size-dependent luminescence of the carbonyl-substituted derivatives. The present study can be expected to provide useful insights into developing diverse multi-stimuli-responsive luminescent organic crystals and thus accelerate the practical applications of luminescent sensor systems.
Virtues of Volatility: A Facile Transesterification Approach to Boronic Acids
Hinkes, Stefan P.A.,Klein, Christian D.P.
supporting information, p. 3048 - 3052 (2019/05/10)
Boronic acids are an increasingly important compound class for many applications, including C-C bond formation reactions, medicinal chemistry, and diagnostics. The deprotection of boronic ester intermediates is frequently a problematic and inefficient step in boronic acid syntheses. We describe an approach that highly facilitates this transformation by leveraging the volatility of methylboronic acid and its diol esters. The method is performed under mild conditions, provides high yields, and eliminates cumbersome and problematic purification steps.
THERANOSTIC AGENTS
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Page/Page column 26-27, (2018/12/13)
A theranostic agent can be used in both photoacoustic imaging (PAI) and photothermal therapy (PTT) applications. The theranostic agent can include a small molecule, organic compound with absorption in the near-infrared (NIR) interrogation window (700-900 nm). The compound can be a biocompatible organic nanoparticle (ONP). The theranostic agent can be effectively used in PAI and PAI-guided PTT applications. The theranostic agent can be administered to a patient to locate a tumor site in the patient using invivo imaging techniques. Once the tumor site has been determined, the tumor site can be irradiated with near-infrared light to stop or inhibit the growth of the tumor.