Autor: Morawski, Olaf - Prolib Integro

Skocz do pozycji: 1.

Tytuł:: Strongly fluorescent indolizine-based coumarin analogs
Autorzy:: Szewczyk, Adam
Morawski, Olaf
Deperasińska, Irena
Gryko, Daniel T.
Badaro, Jaqueline S. A.
Wrzosek, Antoni
Wydawca:: Partner Organisations 2024
Cytata wydawnicza:: Org. Chem. Front., 2024, 11, 6627–6641 ; https://doi.org/10.1039/D4QO01216J
Opis:: Polish National Science Center, Poland (grants OPUS 2020/37/B/ST4/00017 and HARMONIA 2018/30/M/ST5/00460); European Union's Horizon 2020 research and innovation programme under the Marie Skłodowka-Curie grant agreement no 101007804; Foundation for Polish Science (TEAM POIR.04.04.00-00-3CF4/16-00); Interdisciplinary Center for Mathematical and Computational Modeling (ICM) University of Warsaw under computational allocation G95-1734.
It is now possible to prepare 2-oxo-2H-pyrano[2,3-b]indolizine-3-carboxylates with an ordered arrangement of various substituents directly from pyridinium salts and diethyl 2-(ethoxymethylene)malonate, allowing for refined control of their photophysical properties. Facile entry into some previously unknown derivatives is disclosed to demonstrate the potential of this method. The use of substituted picolinium salts, as well as further functionalization of the pyrrole ring, permitted easy introduction of new moieties upon the dye, which enabled fine-tuning of the photophysical properties. The obtained dyes possess absorption and emission spectrum in the blue–green region and fluorescence quantum yields reaching 92%. The parent 2-oxo-pyrano[2,3-b]indolizine-3-carboxylate turned out to be an electron-deficient system with a low-lying LUMO, an electronic transition energy of 2.7 eV and possessing a large oscillator strength. Almost complete overlap of the HOMO and LUMO in the 2-oxo-pyrano[2,3-b]indolizine core is responsible for the large fluorescence quantum yields for almost all prepared derivatives. The reason for maintaining the large emission intensity in polar solvents is that the increase in the dipole moment is accompanied with a significant change in its orientation in space. Fluorescence imaging studies have proven that 2-oxo-pyrano[2,3-b]indolizines penetrate the membrane of living cells. A positively charged analog was synthesized and used to stain intracellular organelles in the H9c2 cell line. This compound did not penetrate the cell membrane, however after permeabilization, it specifically stained the nucleus.
Dostawca treści:: Repozytorium Centrum Otwartej Nauki

Artykuł

na półce

Skocz do pozycji: 2.

Tytuł:: Polarized, V-Shaped, and Conjoined Biscoumarins: From Lack of Dipole Moment Alignment to High Brightness
Autorzy:: Morawski, Olaf
Vygranenko, Kateryna V.
Gryko, Daniel T.
Kielesiński, Łukasz
Deperasińska, Irena
Ouellette, Erik T.
Wydawca:: American Chemical Society
Cytata wydawnicza:: J. Org. Chem. 2022, 87, 5961−5975 . https://doi.org/10.1021/acs.joc.2c00232
Opis:: Polish National Science Center, Poland (OPUS 2020/37/B/ST4/00017) QuantERA programme─project 2017/25/Z/ST2/03038 Foundation for Polish Science (TEAM POIR.04.04.00-00-3CF4/16-00) EU’s Horizon 2020 research and innovation programme under grant agreement no 860762 (MSC ITN CHAIR) Director, Office of Science, Office of Basic Energy Sciences, of the U.S. DOE under contract no. DE-AC02-05CH11231
Eleven conjoined coumarins possessing a chromeno[3,4-c]chromene-6,7-dione skeleton have been synthesized via the reaction of electron-rich phenols with esters of coumarin-3-carboxylic acids, catalyzed by either Lewis acids or 4-dimethylaminopyridine. Furthermore, Michael-type addition to angular benzo[f]coumarins is possible, leading to conjugated helical systems. Arrangement of the electron-donating amino groups at diverse positions on this heterocyclic skeleton makes it possible to obtain π-expanded coumarins with emission either sensitive to, or entirely independent of, solvent polarity with large Stokes shifts. Computational studies have provided a rationale for moderate solvatochromic effects unveiling the lack of collinearity of the dipole moments in the ground and excited states. Depending on the functional groups present, the obtained dyes are highly polarized with dipole moments of ∼14 D in the ground state and ∼20–25 D in the excited state. Strong emission in nonpolar solvents, in spite of the inclusion of a NO2 group, is rationalized by the fact that the intramolecular charge transfer introduced into these molecules is strong enough to suppress intersystem crossing yet weak enough to prevent the formation of dark twisted intramolecular charge transfer states. Photochemical transformation of the dye possessing a chromeno[3,4-c]pyridine-4,5-dione scaffold led to the formation of a spirocyclic benzo[g]coumarin.
Dostawca treści:: Repozytorium Centrum Otwartej Nauki

Artykuł

na półce

Skocz do pozycji: 3.

Tytuł:: N-Aryl substituents have an influence on the photophysics of tetraaryl-pyrrolo[3,2-b]pyrroles
Autorzy:: Banasiewicz, Marzena
Petrykowski, Wojciech D.
Morawski, Olaf
Kałuża, Zbigniew
Gryko, Daniel T.
Barboza, Cristina A.
Wydawca:: Royal Society of Chemistry
Cytata wydawnicza:: Phys. Chem. Chem. Phys., 2026, 28, 2344-2352 // https://doi.org/10.1039/D5CP03474D
Opis:: The photophysics of two series of 1,4-dihydro-tetraaryl-pyrrolo[3,2-b]pyrroles possessing N-aryl substituents with various electronic characteristics was investigated systematically. The molecular structure of these compounds was designed so that their solubility enabled us to study their absorption and emission in a broad range of solvents. The presence of N-4-nitrophenyl substituents is responsible for a weak charge-transfer absorption band and shifts the emission band hypsochromically. At the same time, their presence quenches fluorescence; although if electron-withdrawing substituents are present at positions 2 and 5, this effect is reduced by an order of magnitude. In the case of less electron-withdrawing N-4-cyanophenyl and N-3-cyanophenyl groups, strong emission is present only if the electron-withdrawing groups are located at positions 2 and 5. The combined experimental and computational study points out the existence of a barrier between au (bright) and ag (dark) CT states, the height of which is the key factor governing the fate of these molecules in the excited state. Weaker electronic communication at positions 1 and 4 of the DHPP core is responsible for strong charge separation. Polar solvents favor the formation of transient dipole moments due to excited-state symmetry-breaking, which amplifies the nonradiative deactivation of nitro-TAPPs. A large increase in fluorescence intensity at 77 K suggests that internal conversion is a key channel for non-radiative electronic relaxation. Conversely, moderate to weak electron-donating groups favor strong LE emission.
European Union’s Horizon 2020 Research and Innovation Programunder the Marie Skłodowska-Curie grant agreement no. 101007804; European Research Council (ARCHIMEDES, 101097337); Polish National Science Centre (OPUS 2020/37/B/ST4/00017); Polish high-performance computing infrastructure PLGrid (HPC Center: ACK Cyfronet AGH) grant no. PLG/2024/017465.
Dostawca treści:: Repozytorium Centrum Otwartej Nauki

Artykuł

na półce

Skocz do pozycji: 4.

Tytuł:: Hybrid of Indolizine and Merocyanine—A New Class of Organelle-Specific Dyes
Autorzy:: Park, Juhee
Kandere-Grzybowska, Kristiana
Morawski, Olaf
Gryko, Daniel T.
Badaro, Jaqueline S. A.
Kolygina, Diana V.
Grzybowski, Bartosz
Perkowska, Maja
Deperasińska, Irena
Koszarna, Beata
Wydawca:: Wiley-VCH GmbH
Cytata wydawnicza:: Angew. Chem. Int. Ed. 2025, e202508044 (1 of 8) // https://doi.org/10.1002/anie.202508044
Opis:: Unlocking the potential of electron-rich 2-hydroxyindolizines led to the discovery of a new class of dyes—indolizine-merocyanines (IndMer) and indolizine-cyanines. Tandem Friedel–Crafts alkylation followed by intramolecular nucleophilic aromatic substitution afforded structurally diverse dyes, as both the nucleophilic and electrophilic partners can be broadly modified. A convergent fragment coupling strategy allowed rapid access to these π-conjugated merocyanines in three steps from pyridines. Uniform distribution of the HOMO and LUMO combined with negligible change of dipole moment upon excitation is responsible for the intense orange or red emission of this new family of reasonably photostable dyes in a broad range of solvents. The new merocyanine dyes have the potential to target a variety of organelles—both uncharged and positively charged indolizine–merocyanines localize a subset of cellular lysosomes, positively charged indolizine–cyanine hybrid accumulates in mitochondria, while coumarin–merocyanine shows context-dependent localization to mitochondria and RNA-rich nucleoli of the living cells. Graphical Abstract The new merocyanines and cyanines possessing an indolizine scaffold were synthesized via tandem Friedel–Crafts alkylation followed by nucleophilic aromatic substitution, by leveraging the special reactivity of 2,3,5,6-tetrafluoro-4-hydroxybenzaldehyde. Indolizine scaffold as a donor enables the bathochromic shift of emission independent of solvent polarity, whereas indolizine–cyanine selectively marks mitochondria or RNA-rich nucleoli.
European Union's Horizon 2020 Research and Innovation Program under the Marie Skłodowska-Curie grant agreement no. 101007804 and from European Research Council (ARCHIMEDES, 101097337); Polish National Science Centre (OPUS 2020/37/B/ST4/00017); Interdisciplinary Center for Mathematical and Computational Modeling (ICM) University of Warsaw under computational allocation G98-2100; Institute for Basic Science (IBS-R020-D1).
Early view - online Version of Record before inclusion in an issue.
Dostawca treści:: Repozytorium Centrum Otwartej Nauki

Artykuł

na półce

Skocz do pozycji: 5.

Tytuł:: Synteza i właściwości optyczne amido-kumaryn : [Rozprawa doktorska stanowi monotematyczny cykl publikacji z kometarzem]
Synteza i właściwości optyczne amido-kumaryn [Rozprawa doktorska stanowi monotematyczny cykl publikacji z kometarzem
Autorzy:: Kielesiński, Łukasz
Współwytwórcy:: Gryko, Daniel Tomasz (supervisor)
Morawski, Olaf (promotor pomocniczy)
Morawski, Olaf (auxiliary supervisor)
Gryko, Daniel Tomasz (promotor)
Wydawca:: Instytut Fizyki Polskiej Akademii Nauk
Institute of Physics of the Polish Academy of Science
Powiązania:: Bibliografia przy rozdziałach
Opis:: 58, [202] strony : il., wykr. ; 31 cm
58, [202] p. : il., wykr. ; 31 cm
Dostawca treści:: RCIN - Repozytorium Cyfrowe Instytutów Naukowych

Książka

na półce

Informacja

Wyszukujesz frazę "Morawski, Olaf" wg kryterium: Autor