Alkene Reactions

Hydrogenation (reactants)

H2, metal catalyst (Pd/C, Pt, Rainey Ni)

Hydrogenation (mechanism)

H2 is added syn on either side of the alkene

Hydrogenation (description)

stereospecific - syn

Electrophile Addition (reactants)

H-X nothing else

Electrophile Addition (symmetrical mechanism)

The H is attacked by the double bond and the carbocation is formed on one side. The Cl is added to this side. A racemic product is made

Electrophile Addition (asymmetrical mechanism)

The H is attacked by the double bond and the carbocation is formed on the more substituted side. The Cl is added to this side. A racemic product is made. (regioselective through markovnikov’s rule)

Electrophile Addition (description)

regioselective (Markovnikov = H on less substituted side)

Markovnikov Addition of H-OH, with issues (reactants)

catalytic amount of H2SO4 or TsOH and H2O

Markovnikov Addition of H-OH, with issues (mechanism)

The double bond attacks a proton on the catalyst and a carbocation is formed on the most substituted side. The water attacks here and forms a positively charged H3O+. This is deprotonated by the catalyst.

Markovnikov Addition of H-OH, with issues (description)

regioselective (Markovnikov = H on less substituted side)

Markovnikov Addition of H-OH, with issues (issues)

C+ is achiral so no stereochemistry which causes weird behavior, C+ can go through alkene isomerization. When the alkene deprotonates the H3O+, it can create alkenes through E1. To avoid this you must do the reaction at low temperatures which favor addition, whereas high temperatures favor E1.

Markovnikov Addition of X2 (reactants)

X2, CCl4

Markovnikov Addition of X2 (mechanism)

The double bond attacks one of the X and forms a three membered ring. The other X will break the ring by adding to the more substituted C and breaking the X-C bond on that side. The product will be racemic

Markovnikov Addition of X2 (mechanism)

stereospecific - anti

Markovnikov Addition of X-OH - Hydrohalegenation (reactants)

X2, H2O

Markovnikov Addition of X-OH - Hydrohalegenation (mechanism)

The double bond attacks the X and forms a three membered ring. The water will break the ring by adding to the more substituted C and breaking the X-C bond on that side. The H3O+ is deprotonated by another water. The product will be racemic

Markovnikov Addition of X-OH - Hydrohalegenation (description)

stereospecific - anti, regioselective (Markovnikov = H on less substituted side) hydrohal

Markovnikov Addition of H-OH - oxymercuration - demercuration (reactants)

Step 1) Hg(OAc)2, H2O

Step 2) NaBH4, H2O, NaOH

Markovnikov Addition of H-OH - oxymercuration - demercuration (mechanism)

Step 1 = The double bond attacks the +:HgOAc and forms a three membered ring. The water will break the ring by adding to the more substituted C and breaking the HgOAc-C bond on that side. The H3O+ will be deprotonated by another H2O. The product will be racemic.

Step 2 = Using the step 2 reactants, the HgOAc will be replaced by OH in either anti or syn fashion.

Markovnikov Addition of H-OH - oxymercuration - demercuration (description)

stereospecific - anti, regioselective (Markovnikov = H on less substituted side) oxymerc

Anti-Markovnikov Addition of H-OH - hydroboration-oxidation (reactants)

Step 1) BH3, THF

Step 2) H2O2, NaOH

Anti-Markovnikov Addition of H-OH - hydroboration-oxidation (mechanism)

Step 1 = The double bond attacks the B of BH3 and one of the H’s attacks the more substituted C of the alkene hence the anti-markovnikov. A four membered ring is formed in the transition state in syn fashion. The bonds break and leave a racemic product of BH2 on one C and a H added to the other.

Step 2 = Using the step 2 reactants, the BH2 will be replaced by OH in syn fashion. A racemic product is made

Anti-Markovnikov Addition of H-OH - hydroboration-oxidation (description)

stereospecific - syn in step 1, regioselective (Anti-Markovnikov = H on more substituted side)

Epoxidation - Racemic (reactants)

mCPBA

Epoxidation - Racemic (description)

stereospecifc, not enantioselective, product is racemic

Epoxidation - Racemic other method (mechanism)

Do Markovnikov Addition of X-OH Hydrohalegenation and then do SN2 with NH2. In the SN2 part, steal the H from the OH and then SN2 happens where the O kicks off the X as the LG and the epoxide is formed

Epoxidation - single enantiomer (reactants)

NaOCl (bleach), Jacobsen’s Catalyst

Epoxidation - single enantiomer (description)

enantioselective, stereoselective

Diol Synthesis Epoxidation Opening, Anti-Diol (reactants)

H3O+

Diol Synthesis Epoxidation Opening, Anti-Diol (mechanism)

The oxygen on the epoxide attacks the H on H3O+, becoming positively charged. The water attacks the more substituted C of the alkene breaking the C-O bond on that side. The H3O+ is then deprotonated by another H2O so a anti-diol is created

Diol Synthesis Epoxidation Opening, Anti-Diol (description)

stereospecifc - anti

Diol Synthesis Dihydroxylation, Syn-Diol (reactants)

catalystic OsO4, H2O2

Diol Synthesis Dihydroxylation, Syn-Diol (description)

stereospecific - syn

Ozonolysis Reductive Workup (reactants)

Step 1) O3, -78*C

Step 2) Me2S or NaHSO3

Ozonolysis Reductive Workup (mechanism)

break in half and add a O on the broken part

Ozonolysis Oxidative Workup (reactants)

Step 1) O3, -78*C

Step 2) H2O2

Ozonolysis Oxidative Workup (mechanism)

break in half and add a O on the broken part. Any D or H get’s turned into OH