Orgo Ch 10 Addition Reactions

Hydrohalogenation conditions/entropy

low temperature, adds an alkene + Hx, decrease entropy

Elimination conditions/entropy

high temperature, increase entropy

Reagents used for hydrohalogenation

HBr OR HBr & ROOR (peroxide)

hydrohalogenation products using just HBr

markovnikov — hydrogen joins to less substituted carbon

hydrohalogenation products using HBr and ROOR

antimarkovnikov/free radical addition — hydrogen joinds to more substituted carbon

syn v. anti addition

syn: bonds form on same face of alkene

anti: bonds form on opposite faces of alkene

hydrohalogenation reaction mechansim

reagents used in acid-catalyzed hydration reactions

H2O, H3O+, H2SO4

products from acid-catalyzed hydration

markovnikov

use of dilute H2SO4 in acid-catalyzed hydration

H2O acts as a nucleophile, addition/breaking alkene

use of concentrated H2SO4 in acid-catalyzed hydration

H2SO4 protonates the -OH, elimination, forms alkene

Acid-catalyzed hydration reaction mechanism

why oxymercuration-demurcuration is sometimes preferres over acid-catalyzed hydration

no carbocation rearrangments

reagents for oxymercuration-demurcuration

1) Hg(OAc)2 (mercury acetate) AND ROH (often H2O)

2) NaBH4 (sodium borohydride)

products of oxymercuration-demurcuration reactions

markovnikov, anti-addition

oxymercuration-demurcuration reaction mechanism

reagents used for hydroboration-oxidation

1) BH3 and THF (hydroboration)

2) H2O2 and NaOH (oxidation)

products of hydroboration-oxidation

antimarkovnikov, syn addition, no rearrangement

hydroboration-oxidation reaction mechanism

hydrogenation reaction what it does generally

gets rid of double bonds, turns alkene to alkane by adding hydrogens

reagents used for hydrogenation

1) H2

2) Pt, Pd, Ni, or wilkinson’s catalyst

product of hydrogenation reactions

neither markovnikov/anti (both positions filled by H), anti-addition, no rearrangement

hydrogenation reaction mechanism

bromination reaction generally what it does

adds 2 halides (either Cl or Br)

bromination reagents

1) X2

2) CCl4 (carbon tetrachloride)

bromination reaction products

neither markovnikov/anti (H occupies both positions), anti-addition, no rearrangement

Reagents for halohydrin formation

similar to bromination

1) X

2) either H2O or ROH

halohydrin reaction products

OH/OR markovnikov, X antimarkovnikov, anti addition, no rearrangement

halohydrin formation reaction mechanism

Dihydroxylation generally what it does

adds 2 hydroxyl (OH) groups to alkene

anti dihydroxylation reagents

1) CH3CO3H (peroxyacetic acid) or MCPBA to form epoxide

2) H3O’s water attacks more sub side to form oxonium

syn dihydroxylation reagents

OsO4 & NMO OR KMnO4 & NaOH

ozonolysis reaction what it generally does

slices alkene into ketone (on middle C) and aldehyde (end Cs), will form C=O bond

reagents for ozonolysis

O3 (ozone) & DMS OR ZN & H2