The six-membered ring in benzene is a perfect hexagon (all carbon-carbon bonds have an identical length of 1.40 Å). Benzene is a unique molecule when it comes to resonance structures. This video will show you how to draw the ‘circle’ of resonance for benzene, as well as resonance intermediates for substituted aromatic compounds including Electron Donating Groups EDG which resonate into the ring and Electron Withdrawing Groups EWG which cause resonance out of the ring. When resonance theory was first applied to understanding the structure of benzene, the key feature seemed to be a resonance hybrid of ring structures containing alternating single and double bonds.
He said that he had discovered the ring shape of the benzene molecule after having a reverie or day-dream of a snake seizing its own tail (this is a common symbol in many ancient cultures known as the Ouroboros or Endless knot). The six-membered ring in benzene is a perfect hexagon (all carbon-carbon bonds have an identical length of 1.40 Å). Here Kekulé spoke of the creation of the theory. This immediately led to attempts to make and study compounds like cyclooctatetraene and cyclobutane. Resonance Structures of Benzene. October 13, 2016 By Leah4sci Leave a Comment. The cyclohexatriene contributors would be expected to show alternating bond lengths, the double bonds being shorter (1.34 Å) than the single bonds (1.54 Å). The cyclohexatriene contributors would be expected to show alternating bond lengths, the double bonds being shorter (1.34 Å) than the single bonds (1.54 Å).