Alkynes Reactions

HX

X = Cl, Br

Hydrohalogenation of Alkynes

Produce Vinyl Dihalide

2 equation HX

X = Cl, Br

Hydrohalogenation of Alkynes (2 equations) Geminal Dihalides

X2 = CH2Cl2

(X2 = Cl2, Br2)

Halogenation of Alkynes (trans-dihalide)

HgSO4, H2O

H2SO4

Oxymercuration of Alkynes

with a ketone

1. Sia2BH • THF

2. H2O2, NaOH, H2O

Hydroboration of Alkynes

Aldehydes addition

O3, H2O

or KMnO4, -OH

Ozonolysis of an Internal Alkyne

Carboxylic acid

KMnO4

neutral

Alkyne Oxidation

Trans -OH and 2 ketones

O3, H2O

or KMnO4, -OH terminal

Ozonolysis of terminal alkyne

carboxylic acid

H2, Pd/BaSO4

Lindlars Catalyst

Cis Hydrogenation of Alkynes

M, NH3

M = Li+, Na+

Trans Hydrogenation of Alkynes

H2, Pd

Hydrogenation of Alkynes with a Metal Catalyst (2 Hydrogens on 2 carbons each)

NaNH2

Deprotonation of Alkynes

1. NaNH2

2. RX

Alkylation of Alkynes

KOH, heat symbol

X = Cl, Br, I for Vicinal

Internal Alkyne Synthesis via Elimination (Vicinal)

KOH, heat symbol

X = Cl, Br, I for Geminal

Internal Alkyne Synthesis via Elimination (Geminal)

NaNH2, heat symbol

(X = Cl, Br, I) (Vicinal)

Internal Alkyne Synthesis via Elimination (Vicinal)

NaNH2, heat symbol

X = Cl, Br, I (Geminal)

Terminal Alkyne Synthesis via Elimination (Geminal)