A homologous series of chiral bis-ketals and mixed hemiketal-ketals with rigid bicyclo[3.3.1]-3,7-dioxanonane skeleton has been prepared. The crystallization mode (conglomerate or racemic compound) was established by chiral HPLC with double UV/polarimetric detection. The study of the solid-state structure by single crystal X-ray diffraction disclosed interesting CH ... pi intermolecular interactions. Hindering of rotation of phenyl groups at (hemi)ketalic centres was found to occur. A H-1-DNMR study gave activation barriers Delta G(#) of 15.9 kcal mol(-1) in the ketalic moiety and 10.3 kcal mol(-1) in the hemiketalic moiety. The experimental results were substantiated by MM and OFT calculations for ground and transition states. (c) 2011 Published by Elsevier B.V.
Bibliografisk informationThe information about affiliations in this record was updated in December 2015.
The record was previously connected to the following departments: Organic chemistry (S/LTH) (011001240)
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