1.  The alkene functional group

         a)  
                    

         b)   Csp² σ bond, Cp-Cp π bond


2.   Synthesis of alkenes

         a)   two elimination reactions

         b)   removal of hydrogen α to a good leaving group


         c)   two common mechanisms E1 and E2


3.   The E-2 Reaction

         a)  

         b)   rate = k[R][B]

                 i)   concerted reaction
                 ii)   bimolecular

         c)   substrate

                 i)   3° > 2° > 1°

         d)   base

                 i)   strong > weak
                 ii)   -OH, -OR

         e)   need a good leaving group

         f)   mechanism


                 i)   product ratios (Z > H)
                 ii)   why?

                         a)   thermodynamics
                         b)   electronic

                 iii)   increase H

                         a)   large, bulky base

                                

         g)   competition with S_N2


4.   The E-1 Reaction

         a)  


         b)   rate = k[RL]

                 i)   2 steps
                 ii)   rds = carbocation formation
                 iii)   unimolecular

         c)   substrate

                 i)   3° > 2° >> 1°
                 ii)   C⁺ formation

         d)   base

                 i)   generally weak base
                 ii)   H₂O, ROH

         e)   leaving group

                 i)   need a good LG
                 ii)   conversion of poor -> good

         f)   mechanism



                 i)   product ration (Z < H)

         g)   completion with S_N1

                 i)   increase & E1 by adding heat


5.   The dehydration of alcohols

         a)   the reaction



         b)   mechanism

                 i)   based on substrate

                         a)   primary - E2
                         b)   2°, 3° - E1
                         c)   within cyclohexanol



                                 1)   note acid catalyst
                                 2)   conversion of poor LG (OH) into good LG (H₂O)
                                 3)   regeneration of catalyst (H₃O⁺)