Open the molecular model file for benzyne and examine the following molecular orbitals: the LUMO (lowest unoccupied molecular orbital), the HOMO (highest occupied molecular orbital), the HOMO-1 (next lower energy orbital), the HOMO-2 (next lower in energy), and the HOMO-3 (next lower in energy).
(a) Which orbital best represents the region where electrons of the additional π bond in benzyne would be found?
(b) Which orbital would accept electrons from a Lewis base on nucleophilic addition to benzyne?
(c) Which orbitals are associated with the six π electrons of the aromatic system? Recall that each molecular orbital can hold a maximum of two electrons.