1. Stability of radicals (lowest to highest)
    • Methyl¬†< primary¬†< secondary <<¬†tertiary
    • 1* benzylic ~ secondary
    • 2* allylic ~tertiary
  2. Three stages of a radical reaction
    • Initiation: creation of radicals
    • Propagation: movement of upaired e-
    • Termination: two radicals form a bond
    • NOTE - propagation step is responsible for the observed reaction
    • NOTE - don't forget ALL POSSIBLE termination steps
  3. Describe why Br2 is more selective than Cl2 in a radical addition
    • The rate determining step is when the radical C is created from the radical halogen
    • This is an exothermic rxn for Cl2, but an endothermic rxn for Br2
    • Since it is endothermic the transition state is actually closer to the products than reactants and will resemble them more (Hammond's Postulate)
  4. What are some alternate methods of radical formation?
    • Peroxide + heat -> 2 RO* (which can cause other radicals)
    • NBS + heat -> succinimide* + Br* (good method for keeping Br* in solution w/o Br2 or HBr
  5. Important things to remember when doing radical rxns
    • Anti-Markovnikov (Br2/HOOH)
    • Radical goes to weakest bond
    • Most stable radical is formed
    • No rearrangement
    • Racemix mixture
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