Details of a Researcher - Yoshioka, Naoki

Papers - Yoshioka, Naoki

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4-Arylethynyl-5-fluorobenzoyl-1-methylimidazole Exhibiting Self-Recovering Mechanofluorochromism and Forming Fluorescence Molecular Glass

Youhei Miura,Kazuki Murai, Kazufumi Yamada, Naoki Yoshioka

Bulletin of the Chemical Society of Japan (公益社団法人日本化学会) 94 ( 10 ) 2444 - 2450 2021.09

Research paper (scientific journal), Joint Work, Accepted

4-Arylethynyl-5-fluorobenzoyl-1-methyl-1H-imidazoles exhibited self-recovering mechanofluorochromism and formed a glass state. Although the solid sampleof the anisyl-substituted 1a and dimethoxyphenyl-substituted 1b exhibited no and blue f luorescence, respectively, they exhibited bluish-green fluorescence after grinding. These compounds recovered the color of their fluorescence after approximately 20s and after 20h, respectively. Both compounds exhibited non-crystalline samples after melting and rapid cooling to room temperature. Based on thermal analysis, it was found 1a and 1b were supercooling liquid and glass, respectively, at room temperature. Both non-crystalline samples exhibited fluorescence at a wavelength longer than that of the solid state. DFT calculations indicated that the bluish-green fluorescence of the ground and noncrystalline samples was derived from the twisted intramolecular charge transfer excitation state.

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V-shaped fluorophores with a 1-methyl-4,5-bis(arylethynyl)imidazole skeleton displaying solid-state fluorescence, acid responsiveness, and remarkable fluorescence solvatochromism

Miura Y., Kobayashi K., Yoshioka N.

New Journal of Chemistry (New Journal of Chemistry) 45 ( 2 ) 898 - 905 2021.01

ISSN 11440546

Novel V-shaped fluorophores with an imidazole skeleton composed of arylethynyl moieties were developed. Their HOMO-LUMO energy gaps were well controlled by the introduction of electron-withdrawing or -donating groups in the aryl moiety. Compounds with different substituents at the 4- and 5-positions were selectively synthesized exploiting the difference in reactivity between the iodo and bromo groups. All compounds synthesized displayed fluorescence not only in solution but also in the solid state. The compound with a donor-acceptor structure displayed a fluorescence maximum with a wavelength over 500 nm and a large Stokes shift of about 150 nm, due to its intramolecular charge transfer character. In the solid state, the synthesized compounds have planar structures, indicating an expansion of π-conjugation. Upon exposure of the compounds in the solid state to acid vapor, the fluorescence of the compounds with acceptor groups was quenched, and that of the others shifted to longer wavelengths.

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Unique Superparamagnetic‐like Behavior Observed in Non‐π‐delocalized Nitroxide Diradical Compounds Showing Discotic Liquid Crystalline Phase

TAKEMOTO YUSA, ZAYTSEVA ELENA, SUZUKI KATSUAKI, YOSHIOKA NAOKI, TAKANISHI YOICHI, FUNAHASHI MASAHIRO, YUCHIDA OSHIAKI, AKITA TAKUYA, PARK JAYEONG, SATO SHUICHI, CLEVERS SIMON, COQUEREL GÉRARD, AZHUKIN DMITRII G., SHIMONO SATOSHI, SUGIYAMA MASAHITO, TAKAHASHI HIROKI, YAMAUCHI JUN, TAMURA RUI

Chemistry A European Journal (Wiley) 24 2018.10

Research paper (scientific journal), Joint Work, Accepted

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Magneto-Structural Correlation of Cyano-Substituted 3-tert-Butyl-1-phenyl-1,2,4-benzotriazin-4-yl: Spin Transition Behaviour Observed in a 6-Cyano Derivative

TAKAHASHI YUSUKE, TSUCHIYA NAOYA, MIURA YOUHEi, YOSHIOKA NAOKI

New Journal of Chemistry 42 ( 12 ) 9949 - 9955 2018.06

Research paper (scientific journal), Joint Work, Accepted

New cyano-substituted 3-tert-butylbenzotriazinyls, 7CN and 6CN, were synthesized and their spectroscopic properties and magneto-structural correlation were investigated. The radical 7CN formed a 1D columnar structure and displayed an antiferromagnetic interaction along the column (J = -15.8 cm^-1). The 6-cyano substituted radical 6CN also formed a 1D columnar structure and exhibited a reversible spin transition at ca. 284 K in the range of 6 K. The molecular arrangements in the high-temperature phase (300 K) and low-temperature phase (263 K) were evaluated by X-ray crystallographic analysis and the molecules slightly rotated while remaining in the 1D columnar structure, resulting in a phase transition. The spin transition behaviour was caused by the structural phase transition, which was consistent with the DSC and computational studies.

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Magnetic Interactions through a Nonconjugated Framework Observed in Back‐to‐Back Connected Triazinyl–Nitroxyl Biradical Derivatives

TAKAHASHI YUSUKE, MATSUHASHI RYO, MIURA YOUHEI, YOSHIOKA NAOKI

Chemistry A European Journal (Wiley) 24 7939 - 7948 2018.05

Research paper (scientific journal), Joint Work, Accepted

Three hetero-biradical derivatives, with the structure of a back-to-back connected benzotriazinyl and tetramethyl or tetraethylisoindoline N-oxyl sharing a common benzo ring, 1-tBu, 1-Ph, and 2-tBu, were synthesized and characterized by single-crystal X-ray analyses, variable-temperature magnetic susceptibility studies, and DFT calculations. Although these radical derivatives form a columnar or chained assembly in the solid state, magnetic measurements of diluted samples in the polymer matrices and computational result simply that the magnetic properties of the polycrystalline sample can be explained by a two-spin system with an intramolecular antiferromagnetic interaction. The moderately strong intramolecular antiferromagnetic interactions can be interpreted by a through-bond interaction through the nonconjugated framework and/or through-space interactions based on molecular orbital theory. The strong distance dependency between the N-O spin site and vinylic carbon atoms indicates that the orbital interaction plays an important role in the intramolecular magnetic interaction.

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5,12-Diacetyl-5,12-dihydroquinoxalino[2,3-b]quinoxalines; Their Solid State Fluorescence, AIE Properties, and Orbital Switching by Substituent Effect

MIURA YOUHEi, YOSHIOKA NAOKI

Chemistry An Asian Journal (Wiley-VCH) 13 ( 13 ) 1683 - 1687 2018.05

Research paper (scientific journal), Joint Work, Accepted

The compound 5,12-diacetyl-5,12-dihydroquinoxalino[2,3-b]quinoxaline 1a and its derivatives were prepared, and their solid and solution state spectroscopic properties were studied; 1a shows stronger fluorescence in solution than in the solid state due to aggregation caused by self-quenching. Phenyl or alkoxy substituted derivatives 1b–d show solid state fluorescence with moderate quantum yields of about Φ = 0.12~0.15, although these are 0.01~0.07 in solution. The spectroscopic properties of alkoxy substituted derivatives were hardly changed compared to 1a and 1b, although 1a and 1b have similar absorption and fluorescence maxima in solution and in the solid state. DFT calculations indicate that orbital switching occurs between HOMO and HOMO-1 and HOMO-2 due to orbital interactions with introduced substituents. Crystal structure analysis revealed that the molecules have bent structures around tertiary nitrogen atoms and form a characteristic dimeric structure.

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In Silico Study, Synthesis, and Cytotoxic Activities of Porphyrin Derivatives

KURNIAWAN FRANSISKA, MIURA YOUHEI, KARTASASMITA EMRAN RAHMANA, YOSHIOKA NAOKI, MUTALIB ABDUL, TJAHJONO DARTONO H.

Pharmaceuticals (MDPI) 11 ( 1 ) UNSP8 2018.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 1427-8247

Five known porphyrins, 5,10,15,20-tetrakis(p-tolyl)porphyrin (TTP), 5,10,15,20-tetrakis(p-bromophenyl)porphyrin (TBrPP), 5,10,15,20-tetrakis(p-aminophenyl)porphyrin (TAPP), 5,10,15-tris(tolyl)-20-mono(p-nitrophenyl)porphyrin (TrTMNP), 5,10,15-tris(tolyl)-20-mono(p-aminophenyl)porphyrin (TrTMAP), and three novel porphyrin derivatives, 5,15-di-[bis(3,4-ethylcarboxymethylenoxy)phenyl]-10,20-di(p-tolyl)porphyrin (DBECPDTP), 5,10-di-[bis(3,4-ethylcarboxymethylenoxy)phenyl]-15,20-di-(methylpyrazole-4-yl)porphyrin (cDBECPDPzP), 5,15-di-[bis(3,4-ethylcarboxymethylenoxy)phenyl]-10,20-di-(methylpyrazole-4-yl)porphyrin (DBECPDPzP), were used to study their interaction with protein targets (in silico study), and were synthesized. Their cytotoxic activities against cancer cell lines were tested using 3-(4,5-dimetiltiazol-2-il)-2,5-difeniltetrazolium bromide (MTT) assay. The interaction of porphyrin derivatives with carbonic anhydrase IX (CAIX) and REV-ERBβ proteins were studied by molecular docking and molecular dynamic simulation. In silico study results reveal that DBECPDPzP and TrTMNP showed the highest binding interaction with REV- ERBβ and CAIX, respectively, and both complexes of DBECPDPzP-REV-ERBβ and TrTMNP-CAIX showed good and comparable stability during molecular dynamic simulation. The studied porphyrins have selective growth inhibition activities against tested cancer cells and are categorized as marginally active compounds based on their IC50.

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Synthesis and Magnetic Properties of Stable Radical Derivatives Carrying a Phenylacetylene Unit

MIYASHIRO SHOGO, ISHII TOMOAKI, MIURA YOUHEI,YOSHIOKA NAOKI

Molecules (MDPI) 23 ( 2 ) No. 371 2018.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 1420-3049

A nitronyl nitroxide derivative, 2-phenylethynyl-4,4,5,5-tetramethyl-4,5-dihydro-1H-imidazol-1-oxyl-3-oxide (1), and two verdazyl derivatives carrying a phenylacetylene unit, 1,5-diphenyl-3-phenylethynyl-6-oxo-1,2,4,5-tetrazin-2-yl (2) and 1,5-diisopropyl-3-phenylethynyl-6-oxo-1,2,4,5-tetrazin-2-yl (3), were synthesized and their packing structures were studied by X-ray crystallographic analysis and magnetically characterized in the solid state. While 1 and 3 had an isolated doublet spin state, 2 formed an antiferromagnetically coupled pair (2J/kB = −118 K). Density functional theory (DFT) calculations reveal that the spin density polarized in the phenyl group decreases as the dihedral angle between the phenyl ring and radical plane increases.

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Magnetic Interaction Observed in Hetero Biradical Derivatives Containing a 2,2,5,5-Tetramethylpyrrolin-1-yloxyl Unit as a Localized Spin Center

TAKAHASHI YUSUKE, MIURA YOUHEI,YOSHIOKA NAOKI

ChemPhysChem (Wiley) 19 ( 2 ) 175 - 179 2018.01

Research paper (scientific journal), Joint Work, Accepted, ISSN 1439-7641

The magneto‐structural correlation of hetero biradical derivatives containing a 2,2,5,5‐tetramethylpyrrolin‐1‐yloxyl unit as a localized spin center and a verdazyl or nitronyl nitroxide radical is reported. The magnetic susceptibility measurement revealed that the verdazyl attached biradical 1 exhibits ferromagnetic interaction, whereas antiferromagnetic interaction is observed for nitronyl nitroxide attached biradical 2. An EPR study in toluene glass matrix suggests that both 1 and 2 have a ground triplet state. DFT calculations predict that there is intramolecular ferromagnetic interaction for both biradicals. The computation also suggests that the intramolecular magnetic interaction is weaker with larger dihedral angle between pyrroline ring and verdazyl ring/O−N−C−N−O plane of nitronyl nitroxide. The computations of model compounds 3 and 4 suggest that spin polarization on vinylic moiety without distribution of SOMO might be an essential condition for the intramolecular ferromagnetic interaction.

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Computational study of imidazolylporphyrin derivatives as a radiopharmaceutical ligand for melanoma

Kurniawan F., Kartasasmita R., Yoshioka N., Mutalib A., Tjahjono D.

Current Computer-Aided Drug Design (Current Computer-Aided Drug Design) 14 ( 3 ) 191 - 199 2018

ISSN 15734099

© 2018 Bentham Science Publishers. Background: Melanoma is the most aggressive type of skin cancer. Metastatic melanoma is extremely difficult to treat with current therapy methods such as surgery. On the other hand, it is a good opportunity to develop a radiopharmaceutical using a radionuclide such as Technetium (Tc) for diagnostic and Rhenium (Re) for therapeutic purposes. T3,4BCPP has been be used as a radioimaging agent for melanoma cancers experimentally. The aim of the present research was to design new imidazolylporphyrin derivatives with better selectivity and higher affinity than those of T3,4BCPP by molecular modeling. Methods: Eight types of Re-and Tc-labeled imidazolylporphyrins were docked to Fibroblast Growth Factor Receptor 1 (FGFR1, PDB ID: 5AM6) using AutoDock 4.2. FGFR1 was simulated by Molecular Dynamic (MD) simulation for 30 ns using NAMD 2.10 at 37 °C. The obtained conformations were then applied in a molecular docking simulation. Dovitinib (natural ligand of FGFR1), Re-and Tc-T3, 4BCPP were used as references. Results: The MD simulation resulted in an RMSD of 3.8 Å. From all the studied imidazolylporphyrin derivatives, Tc-cD3, 4BCPMIP and Re-cD3, 4BCPIP had the best docking parameter. Tc-cD3, 4BCPMIP had a free binding energy of 4.06 kcal/mol, while that of Re-cD3, 4BCPIP was 4.35 kcal/mol. Conclusion: It is concluded that cD3,4BCPMIP and cD3,4BCPIP are two potential candidate ligands for a melanoma radiopharmaceutical kit.

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A Selective Distance-Based Paper Analytical Device for Copper(II) Determination Using a Porphyrin Derivative

PRATIWI RIMADANI, NGUYEN MICHAEL P., IBURAHIM SLAMET, YOSHIOKA NAOKI, HENRY CHARLES S., TJAHJONO DARTONO H.

Talanta (Elsevier) 174 493 - 499 2017.11

Research paper (scientific journal), Joint Work, Accepted, ISSN 0039-9140

Meso-tetrakis(1,2-dimethylpyrazolium-4-yl)porphyrin sulfonate (TDMPzP), a water-soluble porphyrin derivative, was synthesized and used as a colorimetric reagent for Cu2+ detection on a microfluidic paper-based analytical device (mu PAD) using distance-based quantification. TDMPzP showed a high selectivity for Cu2+ detection in aqueous solutions. When Cu2+ was added to the TDMPzP under acidic conditions, a color change from green to a pink was observed by the naked eye. Under optimized conditions, the application of this system to a distance-based mu PAD exhibited good analytical response. The presence of common metal ions (Al3+, Fe3+, Mg2+, Co2+, Mn2+, Zn2+, Pb2+, Cd2+, Sn2+, and Ni2+) did not interfere with Cu2+ detection within reasonable tolerance ratios. The lowest concentration of copper that could be measured was 1 mg L-1 (1 ppm) which meets the requirements for drinking water contamination regulations from the US Environmental Protection Agency (EPA) and World Health Organization (WHO) guidelines for drinking water. Real drinking water samples were analyzed to confirm the practical application of this system and the results showed good agreement with ICP-MS data. This distance-based mu PAD based on TDMPzP for Cu2+ detection is convenient and effective for real-time drinking water analysis.

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Synthesis and Physicochemical Properties of Methoxy-Substituted Diphenyldihydroacridine and Its Si and Ge Bridged Analogues and Corresponding Nitroxide Radical Derivatives

SUZUKI RYOTA, TADA REIKI, MIURA YOUHEI, YOSHIOKA NAOKI

Journal of Molecular Structure 1106 399 - 406 2016.02

Research paper (scientific journal), Joint Work, Accepted

Three dihydroacridine analogues, 2,7-dimethoxy-9,10-dihydro-9,9-diphenylacridine (1-C), 2,8-dimethoxy-10,10-diphenyl-5,10-dihydrophenazasiline (1-Si), and 2,8-dimethoxy-10,10-diphenyl-5,10-dihydrophenazagermine (1-Ge), and corresponding nitroxide radical derivatives, 2,7-dimethoxy-9,10-dihydro-9,9-diphenylacridine-10-oxyl (2-C), 2,8-dimethoxy-10,10-diphenyl-5,10-dihydrophenazasiline-5-oxyl (2-Si), and 2,8-dimethoxy-10,10-diphenyl-5,10-dihydrophenazagermine-5-oxyl (2-Ge) were synthesized in order to study the effect of the Si and Ge bridging atoms on the physicochemical properties of the diaryl nitroxide radical derivatives. These derivatives were stable in non-halogenated solvents and in the solid state. Their structures were crystallographically analyzed and UV-vis, fluorescence, EPR, and cyclic voltammetry measurements were performed to investigate the physicochemical properties of the dihydroacridine analogues and nitroxide radical derivatives.

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Synthesis of Ester-Substituted Dihydroacridine Derivatives and Their Spectroscopic Properties

SUZUKI RYOTA, TADA REIKI, HOSODA TAKUMI, MIURA YOUHEI, YOSHIOKA NAOKI

New Journal of Chemistry 40 ( 3 ) 2920 - 2926 2016.01

Research paper (scientific journal), Joint Work, Accepted

Three dihydroacridine derivatives, 2,7-bis(4-methoxycarbonylphenyl)-9,9-diphenyl-9,10-dihydroacridine (1), 2,8-bis(4-methoxycarbonylphenyl)-10,10-diphenyl-5,10-dihydrophenazasiline (2), and 2,7,9,9-tetraphenyl-9,10-dihydroacridine (3), were prepared and their spectroscopic properties were investigated. These compounds exhibited relatively high quantum yields in a range of solvents. The emission spectra of 1 and 2 displayed large solvatochromic shifts, while the fluorescence solvatochromic behavior was not observed in 3. The intramolecular charge transfer (CT) process from the electron donating moiety at the NH site to the electron withdrawing ester moiety occurs in the excited states of 1 and 2. The increase in the dipole moment induced by the CT process was determined to cause the positive fluorescence solvatochromism. The differences between the excited and ground state dipole moments based on the Lippert-Mataga expression were estimated. The effect of the push-pull substitution in the dihydroacridine pi-conjugated system was also discussed using a computational method.

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Effects of Cyano, Ethynyl and Ethylenedioxy Groups on the Photophysical Properties of Carbazole-Based Porphyrins

MAEDA CHIHIRO, KURIHARA KOSUKE, MASUDA MOTOKI, YOSHIOKA NAOKI

Organic & Biomolecular Chemistry 13 ( 46 ) 11286 - 11291 2015.09

Research paper (scientific journal), Joint Work, Accepted

The synthesis and photophysical properties of cyano and ethynyl substituted carbazole-based porphyrins were investigated. The introduction of ethynyl groups induced red shifts, while that of cyano groups induced blue shifts of their absorption bands, which was supported by MO calculations. Ethylenedioxy-appended porphyrins were also prepared via a coupling reaction. The conjugated and electronic substituent effects on the photophysical properties of the carbazole-based porphyrins have been elucidated by using both experimental results and calculations. Among these porphyrins, the ethylenedioxy-appended selenaporphyrin displayed intensified and red-shifted absorption in the NIR region up to 1178 nm.

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π-Stacked Structure of Thiadiazolo-Fused Benzotriazinyl Radical: Crystal Structure and Magnetic Properties

MIURA YOUHEI, YOSHIOKA NAOKI

Chemical Physics Letters (Elsevier) 626 ( 17 ) 11 - 14 2015.04

Research paper (scientific journal), Joint Work, Accepted

A novel benzotriazinyl radical with a 2,1,3-thiadiazolo fused ring (1,3-diphenyl-1,2-dihydro-[1,2,5]thiadiazolo[3′,4′:3,4]benzo[1,2-e]-1,2,4-triazine-2-yl; NSNBT) was prepared and characterized by ESR measurement, cyclic voltammetry, and X-ray crystallographic analysis. By a detailed study of bond lengths and angles, it was found that the molecular structure of NSNBT borrows characteristics both from 2,1,3-benzothiadiazole and from the unsubstituted benzotriazinyl radical, and the central phenyl ring presents a phenanthrene-type bond alternation. Molecules were shown to be arranged in a π-stacked columnar structure, with columns connected to each other through sulfur-sulfur interactions in the crystal. It exhibited strong antiferromagnetic interactions (J/kB = -434 K) derived from its dimer structure.

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Synthesis and Properties of the 3-tert-Butyl-7-trifluoromethyl-1,4-dihydro-1-phenyl-1,2,4-benzotriazin-4-yl Radical

TAKAHASHI YUSUKE, MIURA YOUHEI, YOSHIOKA NAOKI

New Journal of Chemistry 39 ( 6 ) 4783 - 4789 2015.04

Research paper (scientific journal), Joint Work, Accepted

A novel benzotriazinyl radical, 3-tert-butyl-7-trifluoromethyl-1,4-dihydro-1-phenyl-1,2,4-benzotriazin-4-yl (2), was prepared and its magneto-structural correlation was investigated. An X-ray crystallographic analysis revealed that 2 forms a 1D column assembly, however, pi-pi interaction was not the driving force of the column structure. The magnetic susceptibility obeyed the Curie-Weiss law with C = 0.369 emu K mol(-1) and theta = +0.7 K. The thermal behavior of wmT was described using the 1D ferromagnetic chain model with J/k(B) = +0.91 K.

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Wurster's Blue-type Cation Radicals Framed in a 5,10-Dihydrobenzo[a]indolo[2,3-c]carbazole (BIC) Skeleton: Dual Electrochromism with Drastic Changes in UV/Vis/NIR and Fluorescence

SUZUKI TAKANORI, SAKANO YUTO, TOKIMIZU YUSUKE, MIURA YOUHEI, KATOONO RYO, FUJIWARA KENSHU, YOSHIOKA NAOKI, FUJII NOBUTAKA, OHNO HIROAKI

Chemistry An Asian Journal (Willey) 9 ( 7 ) 1841 - 1846 2014.06

Research paper (scientific journal), Joint Work, Accepted

Electron-donating dihydrobenzindolocarbazoles (BICs) 1 a-c, which adopt planar disk-shaped geometries, were prepared by gold(I)-catalyzed cyclization as a key step. Due to the presence of a 1,4-phenylenediamine (PD) moiety in the framework, they undergo reversible one-electron oxidation to the corresponding Wurster's Blue (WB)-type species that exhibits NIR absorptions up to λ=1200 nm. In the case of the N,N'-dimethyl derivative, cation radical 1 c(+.) is stable enough to be isolated as a salt and X-ray analysis indicated paraquinoid-type bond alternation in the WB core unit, whereas the bond lengths in the peripheral benzene rings are identical to those in the neutral donor. Upon electrochemical interconversion, the redox pairs of 1 a-c and 1 a-c(+.) exhibited an electrochromic response in the UV/Vis/NIR region, which was accompanied by a drastic change in the fluorescence spectrum because only neutral donors 1 a-c are highly emissive (Φ(F) : 0.7-0.8).

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Introduction of Three Aryl Groups to Benzotriazinyl Radical by Suzuki-Miyaura Cross-coupling Reaction

TAKAHIASHI YUSUKE, MIURA YOUHEI, YOSHIOKA NAOKI

Chemistry Letters (Chemical Society of Japan) 43 1236 - 1238 2014.05

Research paper (scientific journal), Accepted

A new radical, 7-phenyl-1,3-bis(4-biphenylyl)-1,4-dihydro-1,2,4-benzotriazin-4-yl (2), was prepared from the iodo group-substituted benzotriazinyl radical 1 with phenyltriolborate salt by the Suzuki–Miyaura cross-coupling reaction at room temperature. An X-ray crystal structural analysis clarified its crystal structure. ESR measurements and DFT calculations revealed that its unpaired electron was more delocalized over the molecule than that of Blatter’s radical due to the substituent effect.

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Synthesis of Carbazole-Based Heterocore-Modified Porphyrins

MAEDA CHIHIRO, MASUDA MOTOKI, YOSHIOKA NAOKI

Organic & Biomolecular Chemistry (Chemical Society) 12 2656 - 2662 2014.02

Research paper (scientific journal), Joint Work, Accepted

Cu(I)-mediated annulation reaction of a 1,1′-(1,3-butadiyne)-8,8′-(2,5-thiophene)-bridged carbazole dimer 10 with amines provided the N-substituted carbazole-based isophlorines 11a–11c. A similar annulation reaction with selenium in the presence of hydrazine monohydrate afforded hetero-core-modified isophlorine 12. The oxidation of 12 generated the corresponding 21-selena-23-thiaporphyrin 13, which exhibited NIR absorption. The intramolecular charge transfer from Se to S was confirmed by the 1H NMR results along with DFT calculations.

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Effective pi-Extension of Carbazole-Based Thiaporphyrins by Peripheral Phenylethynyl Substituents

MAEDA CHIHIRO, MASUDA MOTOKI, YOSHIOKA NAOKI

Organic Letters (American Chemical Society) 15 ( 14 ) 3566 - 3569 2013.07

Research paper (scientific journal), Joint Work, Accepted

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