alkene and alkyne reactions

addition of molecular halogens (br2, cl2)

Br2/Cl2 + inert solvent (CHCl2)

anti-addition

formation of halohydrins

Br2/Cl2 + water or non inert solvent
aka addition of HOCl or HOBr

markovnikov anti addition, bridged halogen, water attacks more substituted side

oxymercuration reduction

1.Hg(OAc)2 + THF/H2O

2.NaBH4 + H2O

markovnikov anti addition, HgOAc bridged, water attacks more substituted side, HGOAc replaced with OH

hydroboration oxidation

1.BH3 + THF

2.H2O2 + NaOH, H2O

anti markovnikov syn addition, boron attaches to less substituted carbon, boron replaced with OH

dihydroxylation

OsO4

OH syn addition

ozonolysis

1.O3

2.(CH3)2S

Cleavage to make ketone and aldehyde

catalytic hydrogenation

H2 and metal catalyst (Pd)

syn addition of hydrogens

acid catalyzed additions for alkenes

H2O or CH3OH + strong acid (H2SO4, HCl)

pi bond attacks h3O+, carbocation formation, H2O attacks carbocation, deprotonated

left with OH

alkylation of acetylide anions

NaNH2 + NH3

Alkyl halide

NaNH2 (sodium amide) attacks H on terminal end of alkyne, carbon on alkyne end is - charged, attacks hydrocarbon attached to a halogen to lengthen molecule via. C-C bonds

alkenes to alkynes

1.NaNH2, NH3 2.H2O or

KOH EtOH delta

anti addition, uses equivalents

addition of hydrogen halides

markovnikov anti addition with no rearrangement

pi bond attacks hydrogen, br/cl/i departs
halogen exhibits resonance and moves electron pair to carbocation
pi bond moves back to halogen and second halogen attacks carbocation

2 halogens on end carbon

hydroboration oxidation of alkynes

1.(sia)2BH + THF

2.H2O2 + NaOH

pi bond attacks boron, B(sia)2 and H on either side of double bond

B(sia) gets replaced with OH group, tautomerization

acid catalyzed hydrations of alkynes

HgSO4, H2SO4 and H2O

markovnikov

uses a bridged mercurnim ion
adds an OH to the more substituted carbon, tautomerization

catalytic reduction of alkynes

H2 + metal catalyst (Pd, Pt, Ni)
or uses lindalar’s catalyst

syn addition
happens twice

dissolving metal reduction of alkynes

sodium metal is used in liquid NH3
makes trans configuration

addition of Br2 and Cl2

Br2/Cl2 and CH2Cl2

anti-addition x2