Creation of antiaromatic compounds by controlling the HOMO-LUMO energy gap

• Project/Area Number: 26620037
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Organic chemistry
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Muranaka Atsuya 国立研究開発法人理化学研究所, 内山元素化学研究室, 専任研究員 (20374902)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Project Status: Completed (Fiscal Year 2015)
• Budget Amount: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2015: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000); Fiscal Year 2014: ¥1,820,000 (Direct Cost: ¥1,400,000、Indirect Cost: ¥420,000)
• Keywords: 反芳香族性

Outline of Final Research Achievements

Cyclic planar compounds with a 4nπ-electron system generally exhibit anti-aromaticity and paratropic ring current effects in their NMR spectra. Although 20π-electron hemiporphyrazines adopt a planar structure, their paratropic ring current effects are weak. In this study, antiaromatic hemiporphyrazines with strong paratropic ring current effects have been synthesized by controlling the HOMO-LUMO energy gap. A combined experimental and computational investigation revealed that there is a linear relationship between the magnitude of ring current effects and the reciprocal of the HOMO-LUMO energy gap.

Research Products

• [Presentation] フタロシアニン系近赤外吸収色素のデザイン技術 (2016)
  • Author(s): 村中 厚哉
  • Organizer: 近畿化学協会機能性色素部会第９０回例会
  • Place of Presentation: 大阪
  • Year and Date: 2016-01-13
  • Invited
• [Presentation] Design, Synthesis, and Electronic Properties of Near-infrared Absorbing Phthalocyanine Analogues (2015)
  • Author(s): A. Muranaka, M. Uchiyama
  • Organizer: 227th ECS Meeting
  • Place of Presentation: Chicago, USA
  • Year and Date: 2015-05-24
  • Int'l Joint Research / Invited
• [Presentation] Electronic Structure Analysis of Cyclic π-electron Molecules: Porphyrinoids and Cycloparaphenylenes (2014)
  • Author(s): A. Muranaka
  • Organizer: The 2nd RIKEN-SJTU Workshop on Energy, Environment and Photonics
  • Place of Presentation: 和光
  • Year and Date: 2014-11-17 – 2014-11-18
  • Invited
• [Presentation] Electronic Structure of Azolehemiporphyrazine (2014)
  • Author(s): A. Muranaka, S. Ohira, N. Toriumi, M. Hirayama, F. Kyotani, Y. Mori, D. Hashizume, M. Uchiyama
  • Organizer: Michinoku International Symposium on Porphyrins, Phthalocyanines and Functional π Molecules
  • Place of Presentation: 蔵王
  • Year and Date: 2014-10-13 – 2014-10-16