Introduction Of Clutch Function Into A Molecular Gear System By Silane -silicate Interconversion

摘要

Since pioneering studies of Mislow et al. and Iwamura et al., bis(9-triptycyl)X systems (X = CH_2, O, NH, SiH_2, PH, etc.) are known as well-designed bevel gear systems. To use the gear systems as a molecular machine, it is desirable to introduce a clutch-declutch mechanism controllable by external stimuli. Silane-silicate interconversion using reversible attachment of a fluoride ion may be a promising option for this purpose. We report herein that the introduction of the clutch-declutch mechanism into a new gear system, a bis(9-triptycyl)difluorosilane derivative, is achieved by the reversible attachment of a fluoride ion and that the corresponding pentacoordinate silicate adopts an unusual trigonal bipyramid (TBP) structure having both the two 9-triptycyl groups at the apical positions against the Muetterties rule.