Chemistry 2210 - Organic Chemistry University of Florida Fall Semester 2010 K. B. Wagener Office In Leigh Hall - Room 318 392 4666 (office Email Address: Wagener @chem.ufl.edu Part 1: Resonance. Tough concept! Resonance spreads out charge (formal charge) over more than one atom, thereby lowering the relative energetics of the molecule. You must work hard at the concept to get things down right. Here are a few pointers: A) Only pi electrons and nonbonded electrons move! Sigma bond electrons do not move. B) Make sure your curved arrows point in the right direction. You’re showing where electrons go, not where they come from. C) There is not a “set” number of contributing structures. You have to work out the proper number of structures for each compound. Part 2: Then, here are the resonance rules in the text (page 43). I find them somewhat convoluted (but they certainly are correct). 1) All contributing (resonance) structures must have the same number of valence electrons
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