Ch. 10 - Addition ReactionsWorksheetSee all chapters
All Chapters
Ch. 1 - A Review of General Chemistry
Ch. 2 - Molecular Representations
Ch. 3 - Acids and Bases
Ch. 4 - Alkanes and Cycloalkanes
Ch. 5 - Chirality
Ch. 6 - Thermodynamics and Kinetics
Ch. 7 - Substitution Reactions
Ch. 8 - Elimination Reactions
Ch. 9 - Alkenes and Alkynes
Ch. 10 - Addition Reactions
Ch. 11 - Radical Reactions
Ch. 12 - Alcohols, Ethers, Epoxides and Thiols
Ch. 13 - Alcohols and Carbonyl Compounds
Ch. 14 - Synthetic Techniques
Ch. 15 - Analytical Techniques: IR, NMR, Mass Spect
Ch. 16 - Conjugated Systems
Ch. 17 - Aromaticity
Ch. 18 - Reactions of Aromatics: EAS and Beyond
Ch. 19 - Aldehydes and Ketones: Nucleophilic Addition
Ch. 20 - Carboxylic Acid Derivatives: NAS
Ch. 21 - Enolate Chemistry: Reactions at the Alpha-Carbon
Ch. 22 - Condensation Chemistry
Ch. 23 - Amines
Ch. 24 - Carbohydrates
Ch. 25 - Phenols
Ch. 26 - Amino Acids, Peptides, and Proteins
Addition Reaction
Acid-Catalyzed Hydration
Epoxide Reactions
Ozonolysis Full Mechanism
Oxidative Cleavage
Alkyne Oxidative Cleavage
Alkyne Hydrohalogenation
Alkyne Halogenation
Alkyne Hydration
Alkyne Hydroboration
Additional Practice
Thermodynamics of Addition-Elimination Equilibria
Stereospecificity vs. Stereoselectivity
Oxymercuration-Reduction Full Mechanism
Hydroboration-Oxidation Full Mechanism
Haloether Formation
Simmons-Smith Addition Mechanism
Regiospecificity of Acid-Catalyzed Ring Openings
Anti Vicinal Dihydroxylation
Ozonolysis Retrosynthesis
LiBr and Acetic Acid for Anti Vinyl Dihaldes
Addition Reagent Facts
Predicting Stereoisomers of Addition Reactions
Addition Missing Reagent
Addition Synthesis
Addition Texas Two-Step
Addition Retrosynthesis
Addition to Concave vs. Convex Rings

Alkynes contain two π-bonds, so when they are exposed to electrophiles, they do exactly what you would expect them to do: they react TWICE with them. 

Halogens Add Twice to Alkynes

Concept #1: General properties of double addition reactions to alkynes.

Keep in mind that for some of these reactions, vinyl carbocations will be created. While unstable, these cannot rearrage, so don’t worry about carbocation rearrangements when reacting with alkynes!

Concept #2: Double hydrohalogenation of alkynes.

General Reaction:

  • Product: gem-dihalides