Chem 8B reagents and products 12-13

Draw an example of the electrophilic addition of H-X

H-Br
- If asymmetrical pi bond, Br and H in mark fashion

• H and Br on either side of pi bond

Draw it

Halogenation (X-X)

Br2 - Alekenes

• Br on either side of pi bond, opposite stereochem

Br2 - Alkynes

• 1 - Alkene formed, Br on either side

• Excess - 2 Br on either side till alkane formed

Halohydration formation (X2 and H2O)

H2O and Br2

• OH adds to more substituted carbon

• Opposite stereo

Acid Catalyzed hydration

H2O and H2SO4

• OH and H in mark. fashion

Oxymercuration reduction of alkynes

H2O, H2SO4, HgSO4

• OH and H in mark. fashion

Oxymercuration reduction of alkenes

1. Hg(OAC)2, H2O, THF 2. NaBH4

• OH and H in mark. fashion

Hydroboration oxidation

1. BH3, THF

2. H2O2, OH-

OH and H in antimark. fashion

Epoxidation

mCPBA

• where pi bond was

Cycloproponation

CH2N2, hv

• Same stereochemistry

• Triangle