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Published on: April 19, 2019
Synthesis of Dimethyldisilabicycloalkanes: Cage-Size Effects on the Relative Stabilities between In,Out and
Wataru Setaka1, Yuto Ikeda1, Yusuke Inagaki1
1Division of Applied Chemistry, Faculty of Urban Environmental Sciences, Tokyo Metropolitan University, 1-1 Minami-Osawa, Hachioji, Tokyo 192-0397, Japan.
None:
In large bicycloalkanes, several in/out forms exist, wherein substituents on the bridgehead atoms are oriented either outside or inside the cage. The relative stability between the in,out and twist-out,out forms, which can interconvert through homeomorphic conversion, was found to depend upon the cage size. The in,out form demonstrated thermodynamic stability in the smaller C10 derivative, whereas the twist-out,out form prevailed in the larger derivatives of C14 and C18 plausibly as a result of dispersion forces among the chains.
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