Co-host: The Chemical Society of Japan, The Society of Synthetic Organic Chemistry, Japan (Cooperation)
Dibenzodehydro[12]annulene 1 has unique properties due to strained ring skeleton. However, 1 easily decomposes at ambient temperature and atmospheric pressure. As a thermally and chemically stable derivative of 1, we report herein the synthesis of silyl-substituted dibenzodehydro[12]annulene 2 and its unique properties due to the steric and the electronic effects of the silyl-substituents.
Compound 1 was reported to be obtained by the coupling reaction of o-diethynylbenzene with a copper reagent in a very low yield together with several cyclic oligomers. On the other hand, the coupling reaction of 2, 3-diethynyl-1, 4-bis(trimethylsilyl)benzene gave only 2 in a good yield. Compound 2 is thermally and photochemically stable and its structure was identified by X-ray analysis. UV-Vis absorption spectra showed significant electronic effects of the silyl-substituents.
