Updated on 2022/05/26

写真a

 
KATO, Kenta
 
Affiliation
Faculty of Science and Engineering, Waseda Research Institute for Science and Engineering
Job title
Junior Researcher(Assistant Professor)
Mail Address
メールアドレス

Concurrent Post

  • Faculty of Science and Engineering   School of Advanced Science and Engineering

Education

  • 2016.04
    -
    2019.03

    Nagoya University   Graduate School of Science   Department of Chemistry  

    Doctoral course

  • 2014.04
    -
    2016.03

    Nagoya University   Graduate School of Science   Department of Chemistry  

    Master course

  • 2010.04
    -
    2014.03

    Nagoya University   School of Science   Department of Chemistry  

Research Experience

  • 2020.10
    -
    Now

    Faculity of Science and Engineering, Waseda University   Organic Synthesis Research Laboratory   Junior Researcher

  • 2020.04
    -
    2020.09

    Faculty of Engineering, Hokkaido University   Hajime Ito, Organoelement Chemistry Lab.   Japan Society for the Promotion of Science, Research Fellowship for Young Scientists, PD

  • 2019.04
    -
    2020.03

    Hokkaido University, Institute for Chemical Reaction Design and Discovery   Postdoctoral Fellows

Professional Memberships

  • 2016.04
    -
    Now

    The Society of Physical Organic Chemistry

  • 2015.10
    -
    Now

    The Chemical Society of Japan (CSJ)

 

Research Areas

  • Synthetic organic chemistry

  • Structural organic chemistry and physical organic chemistry

Papers

  • (9-Isocyanoanthracene)gold(I) Complexes Exhibiting Two Modes of Crystal Jumps by Different Structure Change Mechanisms

    Kenta Kato, Tomohiro Seki, Hajime Ito

    Inorganic Chemistry    2021.04

    Authorship:Lead author

    DOI

  • Double-Helix Supramolecular Nanofibers Assembled from Negatively Curved Nanographenes

    Kenta Kato, Kiyofumi Takaba, Saori Maki-Yonekura, Nobuhiko Mitoma, Yusuke Nakanishi, Taishi Nishihara, Taito Hatakeyama, Takuma Kawada, Yuh Hijikata, Jenny Pirillo, Lawrence T. Scott, Koji Yonekura, Yasutomo Segawa, Kenichiro Itami

       2020.11

    Authorship:Lead author

     View Summary

    The layered structures of graphite and related nanographene molecules play key roles in their physical and electronic functions. However, the stacking modes of negatively curved nanographenes remains unclear, owing to the lack of suitable nanographene molecules. Herein we report the synthesis and one-dimensional supramolecular self-assembly of negatively curved nanographenes without any assembly-assisting substituents. This curved nanographene self-assembles in various organic solvents and acts as an efficient gelator. The formation of nanofibers was confirmed by microscopic measurements, and an unprecedented double-helix assembly by continuous π-π stacking was uncovered by three-dimensional electron crystallography. This work not only reports the discovery of an all-sp<sup>2</sup>-carbon supramolecular π-organogelator with negative curvature, but also demonstrates the power of three-dimensional electron crystallography for the structural determination of submicrometer-sized molecular alignment.

    DOI

  • Six-fold C–H borylation of hexa-peri-hexabenzocoronene

    Mai Nagase, Kenta Kato, Akiko Yagi, Yasutomo Segawa, Kenichiro Itami

    Beilstein Journal of Organic Chemistry   16   391 - 397  2020.03

     View Summary

    Hexa-peri-hexabenzocoronene (HBC) is known to be a poorly soluble polycyclic aromatic hydrocarbon for which direct functionalization methods have been very limited. Herein, the synthesis of hexaborylated HBC from unsubstituted HBC is described. Iridium-catalyzed six-fold C-H borylation of HBC was successfully achieved by screening solvents. The crystal structure of hexaborylated HBC was confirmed via X-ray crystallography. Optoelectronic properties of the thus-obtained hexaborylated HBC were analyzed with the support of density functional theory calculations. The spectra revealed a bathochromic shift of absorption bands compared with unsubstituted HBC under the effect of the sigma-donation of boryl groups.

    DOI

  • Two-step synthesis of a red-emissive warped nanographene derivative via a ten-fold C-H borylation

    Kenta Kato, Hsing-An Lin, Motonobu Kuwayama, Mai Nagase, Yasutomo Segawa, Lawrence T. Scott, Kenichiro Itami

    CHEMICAL SCIENCE   10 ( 39 ) 9038 - 9041  2019.10

    Authorship:Lead author

     View Summary

    The regioselective ten-fold borylation of warped nanographene (WNG: C80H30) was achieved by modifying the reaction conditions of a previously reported Ir-catalyzed C-H borylation, affording decaborylated WNG in high yield (75%) from pristine WNG. The solid-state structure of decaborylated WNG was confirmed by X-ray crystallography. Corresponding decaarylated WNGs containing electron-withdrawing and -donating groups were synthesized from decaborylated WNG using Suzuki-Miyaura cross-coupling reactions to afford the red-emissive warped nanographene derivative.

    DOI

  • Symmetric Multiple Carbohelicenes

    Kenta Kato, Yasutomo Segawa, Kenichiro Itami

    SYNLETT   30 ( 4 ) 370 - 377  2019.03

    Authorship:Lead author

     View Summary

    This account focuses on the synthesis and structures of symmetric multiple carbohelicenes; i.e., fully fused polycyclic aromatic hydrocarbons containing two or more symmetric helicene moieties. Synergies of the multiplexed helicene structures within a -system generate a number of local minima and transition states between each state. Based on recent studies on multiple helicenes, a systematic molecular design for further multiplexed symmetric helicenes is proposed in the last section of this article.

    DOI

  • Synthesis and structural features of thiophene-fused analogues of warped nanographene and quintuple helicene

    Hsing-An Lin, Kenta Kato, Yasutomo Segawa, Lawrence T. Scott, Kenichiro Itami

    CHEMICAL SCIENCE   10 ( 8 ) 2326 - 2330  2019.02

     View Summary

    Thiophene-fused analogues of warped nanographene (WNG) and quintuple helicene (QH) were synthesized via a three-step pi-extension of corannulene. Similar to the synthetic route to WNG, five hexagons and five heptagons were generated by a Scholl reaction of pentakis(thienylphenyl)corannulene to form pentathiaWNG. In contrast, decathiaWNG could not be obtained from pentakis(thienylthienyl) corannulene, and instead decathiaQH was generated from the photocyclization of the precursor. X-ray crystallography of the products revealed their conformations and packing modes in the solid state. The configurational features of decathiaQH were further examined by DFT calculations. The absorption and fluorescence spectra of the sulfur-containing WNG and QH were shifted relative to those of the corresponding sulfur-free analogues.

    DOI

  • Synthesis and Structure of a Propeller-Shaped Polycyclic Aromatic Hydrocarbon Containing Seven-Membered Rings

    Kazuya Kawai, Kenta Kato, Lingqing Peng, Yasutomo Segawa, Lawrence T. Scott, Kenichiro Itami

    ORGANIC LETTERS   20 ( 7 ) 1932 - 1935  2018.04

     View Summary

    The synthesis and structure of a C-3-symmetric propeller-shaped polycyclic aromatic hydrocarbon that bears three seven-membered rings is reported. The synthesis was accomplished in three steps from benzo[c]naphtho-[2,1-p]chrysene, including a Pd-catalyzed intramolecular C-H arylation for the formation of the seven-membered rings. The combination of the helicities (P/M) of the three seven-membered-ring moieties and three [4]helicene moieties affords 24 possible conformers, and two relatively stable conformations were observed by H-1 NMR spectroscopy.

    DOI

  • A Quintuple [6]Helicene with a Corannulene Core as a C-5-Symmetric Propeller-Shaped pi-System

    Kenta Kato, Yasutomo Segawa, Lawrence T. Scott, Kenichiro Itami

    ANGEWANDTE CHEMIE-INTERNATIONAL EDITION   57 ( 5 ) 1337 - 1341  2018.01

    Authorship:Lead author

     View Summary

    The synthesis and structural analysis of a quintuple [6]helicene with a corannulene core is reported. The compound was synthesized from corannulene in three steps including a five-fold intramolecular direct arylation. X-ray crystallographic analysis revealed a C-5-symmetric propeller-shaped structure and one-dimensional alignment in the solid state. The enantiomers of the quintuple [6]helicene were successfully separated by HPLC, and the chirality of the two fractions was identified by CD spectroscopy. A kinetic study yielded a racemization barrier of 34.2kcalmol(-1), which is slightly lower than that of pristine [6]helicene. DFT calculations indicate a rapid bowl-to-bowl inversion of the corannulene moiety and a step-by-step chiral inversion pathway for the five [6]helicene moieties.

    DOI

  • Phenanthro[9,10-a]corannulene by one-step annulative pi-extension of corannulene

    Kenta Kato, Yasutomo Segawa, Kenichiro Itami

    CANADIAN JOURNAL OF CHEMISTRY   95 ( 3 ) 329 - 333  2017.03

    Authorship:Lead author

     View Summary

    The one-step pi-extension of corannulene was achieved using a palladium-catalyzed C-H coupling reaction. The X-ray crystal structure and photophysical properties of the thus formed phenanthro[9,10-a]corannulene (1) were investigated, and the structural properties of 1 were examined by density functional theory calculations. In contrast to dibenzo[g,p]chrysene, the most stable structure of 1 was a butterfly-shaped structure, resulting from the bowl-shaped distortion of the corannulene moiety.

    DOI

  • Synthesis, Properties, and Packing Structures of Corannulene-Based -Systems Containing Heptagons

    Kenta Kato, Yasutomo Segawa, Lawrence T. Scott, Kenichiro Itami

    CHEMISTRY-AN ASIAN JOURNAL   10 ( 8 ) 1635 - 1639  2015.08

    Authorship:Lead author

     View Summary

    Introduction of heptagons into hexagonal carbon lattices can generate negatively curved polycyclic aromatic hydrocarbons, which are of significant interest in the field of exotic molecular nanocarbons. We have successfully synthesized and characterized corannulene-based -systems containing heptagons (4 and 5) as new negatively curved polycyclic aromatic hydrocarbons as well as possible intermediates in the synthesis of warped nanographene 1. The formation of 4 and 5 represents the first example for which a heptagon is formed under Scholl reaction conditions before all hexagons are formed. Even more interestingly, we discovered that the mode and degree of solid-phase intermolecular - interaction can be altered significantly by the degree of ring closure.

    DOI

▼display all

Industrial Property Rights

  • 水溶性ワープドナノグラフェン化合物及びその用途

    伊丹健一郎, 瀬川泰知, 林興安, 東山哲也, 佐藤良勝, 桑田啓子, 加藤健太

    Patent

  • 湾曲ナノグラフェン類縁体の製造方法

    伊丹健一郎, 瀬川泰知, 加藤健太, 畠山泰斗, 川田拓馬

    Patent

Other

  • 危険物取扱者 甲種

     View Summary

    1015 0103 8441

  • エックス線作業主任者

     View Summary

    第60077681601号

Awards

  • ISNA’18 Poster Award

    2019.07   18th International Symposium on Novel Aromatic Compounds   One-Dimensional Self-Assembly of a Negatively Curved Arene

  • 大津会議フェロー 第9期生

    2018.10   公益財団法人 MSD生命科学財団  

  • ポスター賞

    2018.09   第29回基礎有機化学討論会   湾曲ナノグラフェンの一次元自己集積化

  • CSJ Student Presentation Award

    2018.03   Synthesis and structures of a quintuple [6]helicene with a Corannulene Core

  • ISNA’17 Poster Award

    2017.07   17th International Symposium on Novel Aromatic Compounds   Synthesis and Structure of Corannulene-Based Quintuple [6]helicene

Research Projects

  • 単結晶ー単結晶相転移の次元制御による新材料の開発

    日本学術振興会  科学研究費助成事業 特別研究員奨励費

    Project Year :

    2020.04
    -
    2023.03
     

    加藤 健太

  • 巨大な湾曲炭素分子の創製

    日本学術振興会  科学研究費助成事業 特別研究員奨励費

    Project Year :

    2017.04
    -
    2019.03
     

    加藤 健太

     View Summary

    本研究者は前年度までの研究において、コラニュレンを基盤とする新奇湾曲炭素分子の合成と物性評価を行い、三次元に広がる湾曲炭素分子の開拓的研究を行ってきた。これらの成果をもとに、今年度はさらに新奇湾曲炭化水素の合成と性質解明を行った。
    受け入れ研究室ですでに報告されている、「ワープドナノグラフェン(以下WNG)」の合成経路解析をしていく中で、7員環を3つ含むWNG合成中間体が湾曲しているにも関わらず、結晶中で大きなπ-π相互作用をもつことが明らかとなった。そこで、新たにWNG合成中間体からビフェニル基を除いた構造の湾曲π共役骨格である欠損型WNGを合成した。欠損型WNGは有機溶媒に溶解させた後、過飽和状態にさせることでゲル化することが明らかとなった。TEM観察によりファイバーの形成が確認された。この世界初となる無置換PAHの超分子ゲル化剤に関して、学会発表を8件行った。
    巨大湾曲炭素分子へのヘテロ原子の導入による電気的・光学的性質の変化を明らかにするために、WNGと5重ヘリセンのチオフェン縮合類似体の合成を行った。さらに、単結晶X線構造解析および理論化学計算をもちいた構造的特徴の解明を行った。このチオフェン縮合類似体については論文としてChemical Scienceに発表した。
    巨大湾曲炭化水素として複数7員環を含む3回回転対象性のプロペラ分子の合成と構造的特徴の解明を行い、論文1件(Organic Letters)、学会発表1件を行った。
    また昨年度報告した5重ヘリセンに関連して、近年の対象性多重カルボヘリセン研究を総説としてSynlettで発表した。