The whole debate about aromatic bonds is interestingmy organic chemistry colleagues maintain that professional chemists
do not use the circle representation at all but draw benzene in the
traditional double/single way (knowing that this is incorrect)
because reaction mechanisms or electron-pushing diagrams
require this approach. The circle in the hexagon is fine
for 1st year chemistry but presents problems, as this discussion
has brought up, when one goes to polycyclic hydrocarbons, and
of course this approach is rarely consistently applied, for example to the
representation of butadiene, allyl radical, etc where the traditional
structures are always used even tho' they are every bit as wrong
as traditional benzene.
Chemistry Department & Environmental Change Institute
National University of Ireland, Galway::Ireland
