Acta Phys. -Chim. Sin. ›› 2017, Vol. 33 ›› Issue (6): 1253-1260.doi: 10.3866/PKU.WHXB201702212

• ARTICLE • Previous Articles     Next Articles

Synthesis and Properties of a Series of Dinaphthosiloles

Hong-Mei QU1,*(),Ze-Peng CHONG1,Xu CHEN2,Yi-Can MEN1,Hai-Jiao SHEN1   

  1. 1 Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, Tianjin 300072, P. R. China
    2 Tianjin Kingsrial S & T Company, Limited, Tianjin 300384, P. R. China
  • Received:2016-12-21 Published:2017-05-19
  • Contact: Hong-Mei QU E-mail:ququhongmei@126.com
  • Supported by:
    the National Natural Science Foundation of China(21102099)

Abstract:

Siloles constitute an important emerging class of photoluminescent materials. A series of compounds consisting of silole cores and fused naphthalene were synthesized and characterized:6, 6-dimethyl-1, 2, 3, 4, 8, 9, 10, 11-octapropyl-6H-dinaphtho[2, 3-b:2', 3'-d]silole, 1, 2, 3, 4, 8, 9, 10, 11-octabutyl-6, 6-dimethyl-6H-dinaphtho[2, 3-b:2', 3'-d]silole, 6, 6-diphenyl-1, 2, 3, 4, 8, 9, 10, 11-octapropyl-6H-dinaphtho[2, 3-b:2', 3'-d]silole, and 1, 2, 3, 4, 8, 9, 10, 11-octabutyl-6, 6-diphenyl-6H-dinaphtho[2, 3-b:2', 3'-d]silole. These dinaphthalene-fused siloles were synthesized from diiodonaphthalene, which was prepared by a direct coupling method. Subsequent reaction in the presence of n-butyllithium yielded 3, 3'-diiodo-2, 2'-binaphthalene. Direct substitution of two chloride ions from Ph2SiCl2 or Me2SiCl2 with 3, 3'-dilithio-2, 2'-binaphthalene then yielded the multi-substituted silole. Nuclear magnetic resonance spectroscopy and high-resolution mass spectrometry were used to characterize the structures of the siloles. Their optical and electronic properties were investigated using ultraviolet-visible absorption spectroscopy, photoluminescence spectroscopy, cyclic voltammetry, and density functional theory calculations. The dinaphthalene-fused siloles exhibited similar absorption and emission peaks. Their deep highest occupied molecular orbital level at approximately -5.5 eV indicated that they were chemically stable. Differential scanning calorimetry and thermogravimetric analysis indicated that the siloles were stable up to 309℃. A multilayer electroluminescent device was fabricated using 1, 2, 3, 4, 8, 9, 10, 11-octabutyl-6, 6-dimethyl-6H-dinaphtho[2, 3-b:2', 3'-d]silole as a light-emitting layer. The resulting device produced bright blue emission, indicating that these siloles may be suitable materials in organic light-emitting devices.

Key words: Dinaphthosilole, Coupling reaction, Lithiation reaction, Cyclic voltammetry, Thermogravimetric analysis, Organic electroluminescent device