Photochemical and thermal reactions of a kinetically stabilized 9-silaanthracene: the first spectroscopic observation of a 9,10-Dewar-9-silaanthracene isomer

Akihiro Shinohara; Nobuhiro Takeda; Norihiro Tokitoh

doi:10.1021/ja036106m

Photochemical and thermal reactions of a kinetically stabilized 9-silaanthracene: the first spectroscopic observation of a 9,10-Dewar-9-silaanthracene isomer

J Am Chem Soc. 2003 Sep 10;125(36):10804-5. doi: 10.1021/ja036106m.

Authors

Akihiro Shinohara¹, Nobuhiro Takeda, Norihiro Tokitoh

Affiliation

¹ Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan.

PMID: 12952457
DOI: 10.1021/ja036106m

Abstract

A kinetically stabilized 9-silaanthracene (1) underwent unique photochemical and thermal reactions to afford 9,10-Dewar-9-silaanthracene 2a and the head-to-tail [4 + 4] dimer 3, respectively. The structure of 2a was confirmed by 1H, 13C, and 29Si NMR spectra, and the kinetic parameters for the thermal reversion of 2a to 1 were obtained by the measurement of UV/vis spectra. The dimer 3 was thermally stable, and the molecular structure of 3 was determined by X-ray crystallographic analysis. It was experimentally demonstrated for the first time that 9-silaanthracene, as well as anthracene, can afford either the Dewar isomer or [4 + 4] dimer, depending on the reaction conditions.