1. CH 8-2 Acid-Catalyzed Electrophilic Addition of H2O and ROH to Alkenes
(1) Electrophilic Addition of HX (HCl & HBr) -Carbocation mechanism -Regioselective: Markovnikov’s Rule -Non-stereospecific reaction -Rearrangements possible
(2) Electrophilic Addition of H2O and ROH -Acid catalysis -Carbocation mechanism -Rearrangements possible
(3) Electrophilic Addition of Br2 and Cl2 to alkenes -”Halonium ion” mechanism -No carbocation -Stereospecific reaction

2. Mechanism of H2O Addition: Alkene Hydration
(1) H2SO4 (strong acid) provides a reactive H+ electrophile.
(2) A carbocation is formed (non-stereospecific) giving a racemic mixture; rearrangements are possible.
(3) H2O is the nucleophile, and an acid/base neutralization step is needed to give neutral alcohol product and to regenerate the acid catalyst.

3. Mechanism of H2O Addition: Alkene Hydration