Direct borylation of terrylene and quaterrylene

Beilstein Journal of Organic Chemistry

Keiji Uehara¹  Haruka Kano¹  Hiroko Yamada¹  Naoki Aratani¹  Hironobu Hayashi¹  Kyohei Matsuo¹ 

[1] Division of Materials Science, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama-cho, Ikoma 630-0192, Japan;

关键词: borylation;    π-conjugation;    oligorylene;    single crystal x-ray structure;    solubility;   

DOI  :  10.3762/bjoc.16.58

来源: DOAJ

【 摘 要 】

The preparation of large rylenes often needs the use of solubilizing groups along the rylene backbone, and all the substituents of the terrylenes and quaterrylenes were introduced before creating the rylene skeleton. In this work, we successfully synthesized 2,5,10,13-tetrakis(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)terrylene (TB4) by using an iridium-catalyzed direct borylation of C–H bonds in terrylene in 56% yield. The product is soluble in common organic solvents and could be purified without column chromatography. Single crystal X-ray diffraction analysis revealed that the terrylene core is not disturbed by the substituents and is perfectly flat. The photophysical properties of TB4 are also unchanged by the substituents because the carbon atoms at 2,5,10,13-positions have less coefficients on its HOMO and LUMO, estimated by theoretical calculations. Finally, the same borylation reaction was applied for quaterrylene, resulting in the formation of soluble tetra-borylated quaterrylene despite a low yield. The post modification of rylenes enables us to prepare their borylated products as versatile units after creating the rylene skeletons.

【 授权许可】

Unknown