Applied Chemistry for Engineering (공업화학)

The Korean Society of Industrial and Engineering Chemistry (한국공업화학회)
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Synthesis and Photoluminescence Properties of Heteroleptic 9-Arylated Carbazole Iridium(III) Complexes

9-Arylated Carbazole을 주리간드로 사용하는 Heteroleptic Iridium(III) 착물의 합성과 분광학적 특성

  • Oh, Se Hwan (Department of Chemistry, Chungnam National University) ;
  • Yum, Eul Kgun (Department of Chemistry, Chungnam National University) ;
  • Kim, Younghoon (Department of Chemistry, Chungnam National University) ;
  • Im, Yung-Jae (Department of Chemistry, Chungnam National University) ;
  • Heo, Jungseok (Department of Chemistry, Chungnam National University) ;
  • Kim, Yeong-Joon (Department of Chemistry, Chungnam National University)
  • 오세환 (충남대학교 자연과학대학 화학과) ;
  • 염을균 (충남대학교 자연과학대학 화학과) ;
  • 김영훈 (충남대학교 자연과학대학 화학과) ;
  • 임영재 (충남대학교 자연과학대학 화학과) ;
  • 허정석 (충남대학교 자연과학대학 화학과) ;
  • 김영준 (충남대학교 자연과학대학 화학과)
  • Received : 2021.02.17
  • Accepted : 2021.03.15
  • Published : 2021.04.10
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Abstract

N-Heteroaryl carbazoles were synthesized with thermal heating in the presence of Cu(I) catalyst and used as main ligands for the preparation of heteroleptic Ir(III) complexes. In these Ir(III) complexes, 6-membered ring structures of Ir-ligand chelation were found by single crystal X-ray diffraction. The blue shift of photoluminescence for Ir(III) complexes was observed in the case of the strong bond formation between Ir and ancillary ligands. It also has been clearly shown that the higher electron density of heteroaryl aromatic ring influenced shorter maximum photoluminescence wavelength (λmax) of Ir(III) complexes. Since the new Ir(III) complexes showed good phosphorescent emission, they could be potentially used as OLED materials in the emission Layer.

Cu(I) 촉매를 사용하여 열반응을 이용한 N-heteroaryl carbazole을 합성하였고 이를 새로운 heteroleptic Ir(III) 착물 합성을 위한 주리간드로 사용하였다. 새로운 Ir(III) 착물은 일반적인 Ir(III) 착물이 가지는 5각 고리가 아닌 6각 고리를 주리간드와 Ir 금속 결합 사이에서 형성하는 것으로 X-ray 단결정구조를 통해 확인할 수 있었다. 합성한 Ir(III) 착물들은 좋은 인광 특성을 나타내므로 OLED 발광층 재료물질로의 가능성을 보여주었다. 주리간드와 보조리간드 변화에 따른 분광학적 특성을 고찰하였는데 PL 최대 발광 파장(λmax) 변화는 보조리간드가 Ir 금속과 더 강한 결합을 만들수록 단파장 쪽으로 이동하는 것을 발견하였다. 또한, 주리간드에 대해서는 Ir-N 결합을 만드는 헤테로아릴 그룹의 아로마틱고리 전자밀도가 커질수록 단파장 쪽으로 이동하는 경향이 있는 것을 알 수 있었다.

Keywords

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