Templation studies of a tetramethylene-bridged hemicarceplex

This thesis presents a study of template effects on the formation of hemicarceplex 14«guest from two rigid bowl-shaped molecules (tetrol 7) and four tetramethylene bridges. The use of an appropriate template/guest molecule aids in the shell closure of hemicarceplex 14»guest through stabilizing van der Waals and electrostatic interactions during the transition state leading to formation of hemicarceplex 14»guest. By studying the effects of a template molecule on formation of a hemicarceplex, we gain valuable insight into the non-covalent forces that control self-assembling processes. Potential guest molecules varying in size, shape, polarity and symmetry were screened for templating abilities. The reaction was found to be moderately selective towards the template molecule used and competition experiments between successful guest molecules revealed a template ratio that spanned a factor of one thousand. This template effect is compared to those found previously in the formation of hemicarceplex 13 and carceplex 11. [Formula]Science, Faculty ofChemistry, Department ofGraduat