受賞区分：国内学会・会議・シンポジウム等の賞  受賞国：日本国

受賞区分：国内学会・会議・シンポジウム等の賞 

記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Angewandte Chemie - International Edition  

A kinetically-stabilized nitrogen-doped triangulene cation derivative has been synthesized and isolated as the stable diradical with a triplet ground state that exhibits near-infrared emission. As was the case for a triangulene derivative we previously synthesized, the triplet ground state with a large singlet-triplet energy gap was experimentally confirmed by magnetic measurements. In contrast to the triangulene derivative, the nitrogen-doped triangulene cation derivative is highly stable even in solution under air and exhibits near-infrared absorption and emission because the alternancy symmetry of triangulene is broken by the nitrogen cation. Breaking the alternancy symmetry of triplet alternant hydrocarbon diradicals by a nitrogen cation would therefore be an effective strategy to create stable diradicals possessing magnetic properties similar to the parent hydrocarbons but with different electrochemical and photophysical properties.

DOI： 10.1002/anie.202302714

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Dalton Transactions  

Diazulenylmethyl cations bridged with a germanium and tin moiety were synthesized. In these cations, the nature of these elements has impacts on the chemical stability and photophysical properties. Upon aggregation, these cations exhibit absorption bands in the near-infrared region, which are slightly blue-shifted compared to those of silicon-bridged congeners.

DOI： 10.1039/d3dt01491f

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of the American Chemical Society  

We disclose a series of silicon-bridged diazulenylmethyl cations as stable and one-dimensionally π-extended carbocations. Connecting nonbenzenoid azulenes to a carbocation center at an appropriate position while reinforcing a planar arrangement effectively delocalizes a positive charge over the π-conjugated skeleton. This structural constraint endows the carbocations with not only high chemical stability with the pKR+value of around 9.5, despite the absence of any electron-donating substituents, but also an intense absorption in the red region due to the effective enhancement of the transition dipole moment. X-ray crystallographic analysis revealed an offset π-stacked arrangement with the outer seven-membered ring overlapping in a face-to-face manner, in which both the steric bulk of the vertically oriented substituents on the silicon atom and the location of the counter anion should play a crucial role. Reflecting this molecular arrangement, the π-extended cations exhibited a red-shifted absorption in the near-infrared (NIR) region in both the solid state and aggregated state in solution, indicative of the formation of J-aggregates. More pronounced redshifts in the absorption band upon the formation of the aggregates were observed by proper choice of the substituents on the silicon bridge and the counter anions, and the aggregates exhibited sharp fluorescence bands with the maximum emission wavelength exceeding 800 nm. These results demonstrate the impact of the nonbenzenoid aromatic stabilization of a carbocation and the efficacy of the present design strategy for the construction of a promising π-extended cationic motif that can form NIR-absorbing and emissive J-aggregates.

DOI： 10.1021/jacs.2c08372

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担当区分：筆頭著者   記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： org/10.1021/jacs.2c08372

記述言語：日本語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Asian Journal of Organic Chemistry  

Use of an iridium precatalyst with a pyridine-based bidentate ligand allowed the efficient synthesis of benzosilole-fused azulene derivatives via intramolecular dehydrogenative silylation of C−H bonds of azulene. Unique stimuli-responsive fluorescence occurred upon acid treatment by appropriate fusing direction of the azulene ring. TD-DFT calculations suggested that the major radiative decay pathway switched from S2→S0 to S1→S0 upon protonation, and the fusing mode greatly affected the degree of orbital overlap between the two related states that determine emissions of azulene.

DOI： 10.1002/ajoc.202100651

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その他リンク： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/ajoc.202100651

記述言語：英語  

DOI： 10.1021/jacs.1c10680

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Bulletin of the Chemical Society of Japan  

Regiodivergent carbene/alkyne metathesis for the selective synthesis of 2-alkylidenebicyclo[4.1.0]heptanes and 1-alkenyl-bicyclo[3.1.0]hexanes from common 1,6-enynes precursors was demonstrated. The cyclization mode could be switched by simple addition of diamine ligands to control the relative orientation of the approaching chromium Schrock carbene equivalents generated in situ from gem-dichromiomethanes toward triple bonds.

DOI： 10.1246/bcsj.20210305

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担当区分：筆頭著者,　責任著者   記述言語：英語  

出版者・発行元：Chemical Communications  

The authors regret that the name of one of the authors (Shunsuke Moritani) was shown incorrectly in the original article. The corrected author list is as shown above. The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.

DOI： 10.1039/d0cc90516j

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掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemical Communications  

A rare example of cyclization with 5-alkynones, which possess non-polar alkynyl and less electrophilic polar keto carbonyl groups, was demonstrated. The key to promoting carbene/alkyne metathesis followed by alkylidenation with pendant CO double bonds was the Schrock-type nucleophilic reactivity of the generated chromium carbene equivalents from readily available diiodomethanes and CrCl2 by simple heating.

DOI： 10.1039/d0cc03986a

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic Letters  

Treatment of 1,n-enynes with gem-dichromiomethane species prepared in situ from 1,1-diiodomethanes and CrCl2 gave alkenylbicycloalkanes. Alkenylcarbene species, which was generated via [2 + 2] cycloaddition with a triple bond, were intercepted by intramolecular cyclopropanation of a pendant double bond, and alkene metathesis did not proceed. This is a very rare example of transformation of alkynyl CC with gem-dimetalloalkanes. Silyl- and borylcarbene equivalents generated from gem-(dichromio)silyl- and borylmethanes promoted the coupling and cyclization of enediynes as well as 1,n-enynes.

DOI： 10.1021/acs.orglett.0c01304

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic Letters  

Regioselective difunctionalization of two different C-H bonds in one pot using a three-component coupling reaction is described. The reaction order is important for controlling the reactivity and regioselectivity, and the first silylation promotes the second borylation. The introduced formyl, silyl, and boryl functional groups could be independently converted to other functional groups, and the substitution pattern for the resulting benzenes is difficult to access by conventional methods.

DOI： 10.1021/acs.orglett.9b04338

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Chemistry - A European Journal  

A (μ-aryloxo)rhenium complex was isolated and confirmed as a key precatalyst for rhenium-catalyzed ortho-alkenylation (C-alkenylation) of unprotected phenols with alkynes. The reaction exclusively provided ortho-alkenylphenols; the formation of para or multiply alkenylated phenols and hydrophenoxylation (O-alkenylation) products was not observed. Several mechanistic experiments excluded a classical Friedel–Crafts-type mechanism, leading to the proposed phenolic hydroxyl group assisted electrophilic alkenylation as the most plausible reaction mechanism. For this purpose, the use of rhenium, a metal between the early and late transition metals in the periodic table, was key for the activation of both the soft carbon–carbon triple bond of the alkyne and the hard oxygen atom of the phenol, at the same time. ortho-Selective alkenylation with allenes also provided the corresponding adducts with a substitution pattern different from that obtained by the addition reaction with alkynes.

DOI： 10.1002/chem.201903910

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：Organic Letters  

A rhenium complex catalyzed the formation of 2-iodo-1H-indene derivatives through iodine and hydrogen migration of 3-iodopropargyl ethers. The reaction proceeded via generation of 1-iodoalkenylrhenium carbene species by sequential 1,2-iodine and 1,5-hydrogen shifts with readily available precursors under neutral conditions. The reaction mechanism and the reactivity of the generated alkenylcarbene species were also investigated.

DOI： 10.1021/acs.orglett.9b02380

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.joc.9b00598

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.orglett.9b01214

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.orglett.9b00658

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c9cc00223e

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c9cc00270g

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記述言語：日本語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1055/s-0037-1611066

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出版者・発行元：Applied and Environmental Microbiology  

The Legionella Reference Center in Japan collected 427 Legionella clinical isolates between 2008 and 2016, including 7 representative isolates from corresponding outbreaks. The collection included 419 Legionella pneumophila isolates, of which 372 belonged to serogroup 1 (SG1) (87%) and the others belonged to SG2 to SG15 except for SG7 and SG11, and 8 isolates of other Legionella species (Legionella bozemanae, Legionella dumoffii, Legionella feeleii, Legionella longbeachae, Legionella londiniensis, and Legionella rubrilucens). L. pneumophila isolates were genotyped by sequence-based typing (SBT) and represented 187 sequence types (STs), of which 126 occurred in a single isolate (index of discrimination of 0.984). These STs were analyzed using minimum spanning tree analysis, resulting in the formation of 18 groups. The pattern of overall ST distribution among L. pneumophila isolates was diverse. In particular, some STs were frequently isolated and were suggested to be related to the infection sources. The major STs were ST23 (35 isolates), ST120 (20 isolates), and ST138 (16 isolates). ST23 was the most prevalent and most causative ST for outbreaks in Japan and Europe. ST138 has been observed only in Japan, where it has caused small-scale outbreaks; 81% of those strains (13 isolates) were suspected or confirmed to infect humans through bath water sources. On the other hand, 11 ST23 strains (31%) and 5 ST120 strains (25%) were suspected or confirmed to infect humans through bath water. These findings suggest that some ST strains frequently cause legionellosis in Japan and are found under different environmental conditions.

DOI： 10.1128/AEM.00721-18

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DOI： 10.1246/cl.180361

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acscatal.8b01338

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/anie.201801229

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.orglett.7b02956

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/acs.orglett.7b02729

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1021/jacs.7b07487

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DOI： 10.1002/chem.201701579

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1039/c7cc04296e

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記述言語：英語   掲載種別：研究論文（学術雑誌）   出版者・発行元：WILEY-V C H VERLAG GMBH  

Stoichiometric amounts of oxidants are widely used as promoters (hydrogen acceptors) in dehydrogenative silylation of C-H bonds. However, the present study demonstrates that silylative and germylative cyclization with dehydrogenation can proceed efficiently, even without hydrogen acceptors. The combination of [RhCl(cod)](2) and PPh3 was effective for both transformations, and allowed a reduction in reaction temperature compared with our previous report. Monitoring of the reactions revealed that both transformations had an induction period for the early stage, and that the rate constant of dehydrogenative germylation was greater than that of dehydrogenative silylation. Competitive reactions in the presence of 3,3-dimethyl-1-butene indicated that the ratio of dehydrogenative metalation and hydrometalation was affected by reaction temperature when a hydrosilane or hydrogermane precursor was used. Further mechanistic insights of oxidant-free dehydrogenative silylation, including the origin of these unique reactivities, were obtained by density functional theory studies.

DOI： 10.1002/chem.201701579

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1246/cl.170369

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/anie.201701159

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1002/0471264229.os094.20

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総ページ数：1   担当ページ：61-62   記述言語：日本語

総ページ数：3   記述言語：英語

記述言語：英語  

DOI： 10.1021/jacs.7b07487

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記述言語：英語  

DOI： 10.1039/c7cc04296e

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記述言語：英語  

DOI： 10.1002/chem.201701579

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記述言語：英語  

DOI： 10.1246/cl.170369

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記述言語：英語  

DOI： 10.1002/anie.201701159

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DOI： 10.15227/orgsyn.094.0280

開催年月日： 2023年12月

記述言語：英語   会議種別：口頭発表（招待・特別）  

国名：日本国  

開催年月日： 2023年11月

記述言語：英語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2023年10月

記述言語：日本語   会議種別：口頭発表（招待・特別）  

開催地：名古屋   国名：日本国  

開催年月日： 2023年10月

記述言語：日本語   会議種別：公開講演，セミナー，チュートリアル，講習，講義等  

開催地：東京   国名：日本国  

開催年月日： 2023年6月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Raleigh, North Carolina   国名：アメリカ合衆国  

出願番号：特願2014-47900 

特許番号/登録番号：特許Jpn. Kokai Tokkyo Koho (2015), JP 2015-172009 A 20151001 

出願番号：特願Jpn. Kokai Tokkyo Koho (2018), JP 2018-209329