We have been exploring the use of tBu4NF as a means to transform either polymeric T resins or single functional group T8 cages into mixed functional T10 and T12 SQs as illustrated in the two following reactions.1-3 To this end, we have now developed simple, multigram routes to pure PhT8, PhT10 and PhT12. The PhT8 system offers cubic symmetry whereas the PhT10 system offers five fold symmetry and is therefore a very unusual molecule. In contrast, the PhT12 compound has no symmetry. We have also been able to identify and isolate still larger cages as will be discussed. The various cage sizes allow us to explore the effects of symmetry and size on a wide variety of properties. For example, the PhT8 cage brominates almost exclusively in the ortho position. The PhT10 also brominates preferentially in the same position whereas the PhT12 is less selective. Modeling studies seem to explain the observed behavior. We have also used Heck catalytic cross coupling to functionalize the ortho-bromo derivatives of the cages and explored their photophysical properties. References M. Ronchi, S. Sulaiman, N. R. Boston, R. M. Laine, “2010 24, 551–557. M. Z. Asuncion, and R.M. Laine, “Fluoride Rearrangement Reactions of Polyphenyl- and Polyvinylsilsesquioxanes as a Facile Route to Mixed Functional Phenyl,Vinyl T10 and T12 Silsesquioxanes,” J. Am. Chem. Soc. 2010, 132 3723–3736. J. H. Jung, R.M. Laine, “Beads on a chain (BOC) polymers formed from the reaction of NH2PhSiO1.5]x[PhSiO1.5]10-x and [NH2PhSiO1.5]x[PhSiO1.5]12-x mixtures (x = 2-4) with the diglycidyl ether of bisphenol A,” Macromolecules 2011 44, 7263-7272.

F- catalytic rearrangements of silsesequixanes (SQs) and analogs: New cage sizes and unusual reactive properties

251st National Meeting (2016)

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