摘要:
A new approach to the synthesis of cavity molecules is described in which the 1,3 dipolar ACE coupling method is used to join curved frame spacer molecules with obtuse-angled alkenes, The curved frame spacers are comprised of fused norbornenes in which each alternative bridge has the 7-methylene replaced by oxygen. Molecular modeling (AM1) has been used to evaluate the geometry of a selection of bis-crown ether systems, the largest of which has nine norbornane units in the frame, a separation of 20.7 Angstrom and the walls of the cavity having an interplanar angle of 36 degrees.