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

Abstract

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Si σ orbitals and between cage SiSi σ orbitals (see picture).