Using MO theory, show that cycloctatetraene is antiaromatic. Strategy: Use the polygon-and-circle method for deriving the relative energies of the piMO s.

Using MO theory, show that cycloctatetraene is antiaromatic. Strategy

1.	Using MO theory, show that cycloctatetraene is antiaromatic. Strategy: Use the polygon-and-circle method for deriving the relative energies of the piMO s.
Answer» Solution : It is a (4n) `pi` ELECTRON molecule. In the ground STATE. The eight `pi` electrons of cyclooctetraene can be arranged in the `MO s` as shown: SINCE the nonbinding `MO s` are half-filled, a planar form of cyclooctatetraene would, if it existed, be antiaromatic. NOTE that it is in the TRIPLET state, this accounts for its high (olefinic) reactivity.