Persilastaffanes: Design, Synthesis, Structure, and Conjugation between Silicon Cages


  • This work was supported by the Ministry of Education, Culture, Sports, Science, and Technology of Japan (Grant-in-Aid for Scientific Research, grant number 20685004, T.I.) and the JST (Research Seeds Quest Program, T.I.). We thank Prof. Dr. Masahiro Hirama and Prof. Dr. Masahiro Terada (Tohoku University) for measurement time of solid-state NMR spectra and Dr. Toshihito Nakai (JEOL RESONANCE) for recording the solid-state 29Si NMR spectra. D.T. thanks the Global COE program (Molecular Complex Chemistry) for a predoctoral fellowship.


original image

By stepwise catenation of bicyclo[1.1.1]pentasilane units persila[n]staffanes (n=1, 2, and 3) were synthesized as air-stable colorless crystals. A remarkable red-shift of the UV/Vis absorption bands with increasing number of bicyclo[1.1.1]pentasilane units suggests remarkable interactions between bridgehead Si[BOND]Si σ orbitals and between cage Si[BOND]Si σ orbitals (see picture).