AM1 study of conformational properties of (E)-cyclononene

Abstract

The unsymmetrical chair-chair (CC) conformation of (E)-cyclononene is calculated to be 5.7 kJ/mol more stable than the axial-symmetrical twist-chair-chair (TCC) form; the calculated energy barrier for ring inversion of the CC conformation is 45.6 kJ/mol, while the barrier for swivelling of the double bond through the polyethylene bridge is 119.5 kJ/mol.