Important Organic Name Reactions

The following reactions are categorized by their primary function or mechanism, drawn directly from the provided chemical reaction sources.

1. Condensation and Carbonyl Addition Reactions

Aldol Condensation

Two molecules of aldehydes or ketones containing an α-hydrogen condense in the presence of a base (like dilute NaOH) to form β-hydroxyaldehyde or β-hydroxyketone.

Claisen-Schmidt Reaction

A base-catalyzed crossed aldol condensation where an aromatic aldehyde condenses with an aliphatic aldehyde or ketone.

Cannizzaro Reaction

Aldehydes lacking an α-hydrogen atom undergo self-oxidation and reduction (disproportionation) in the presence of concentrated alkali to form an alcohol and a carboxylic acid salt.

Claisen Condensation

Esters containing α-hydrogen atoms undergo self-condensation in the presence of a strong base (like sodium ethoxide) to yield β-keto esters.

Perkin Condensation

An aromatic aldehyde condenses with an aliphatic acid anhydride in the presence of the sodium salt of the same acid to yield an α,β-unsaturated acid (e.g., Cinnamic acid).

Knoevenagel Reaction

Aldehydes and ketones condense with compounds containing active methylene groups (like malonic acid) to form α,β-unsaturated compounds.

Reformatsky Reaction

Zinc and an α-halogenated ester react with a carbonyl compound to yield a β-hydroxy ester.

Wittig Reaction

A carbonyl compound is treated with a phosphorous ylide to form an alken.

2. Reduction Reactions

Clemmensen Reduction

Aldehydes and ketones are reduced to alkanes using Zinc-Mercury amalgam (Zn-Hg) and concentrated HCl.

Wolff-Kishner Reduction

Aldehydes and ketones are reduced to alkanes by heating with hydrazine (NH₂NH₂) and KOH .

Rosenmund’s Reduction

Acid chlorides are reduced to aldehydes using hydrogen and palladised barium sulphate poisoned with sulphur or quinoline.

Birch Reduction

Disubstituted alkynes are reduced with sodium in liquid ammonia to predominantly give trans-alkenes.

Meerwein-Ponndorf-Verley (MPV) Reduction

Ketones are reduced to secondary alcohols by heating with isopropyl alcohol and aluminium isopropoxide.

Stephen’s Reduction

Cyanides are reduced to aldehydes using SnCl₂/HCl followed by hydrolysis.

Sabatier-Senderen’s Reaction

Unsaturated hydrocarbons (alkenes/alkynes) are reduced to alkanes using a nickel catalyst.

3. Oxidation Reactions

Etard Reaction

Aromatic hydrocarbons (like toluene) are oxidized by chromyl chloride (CrO₂Cl₂) to yield aldehydes.

Oppenauer’s Oxidation

Secondary alcohols are oxidized to ketones using aluminium tert-butoxide in excess acetone.

Hydroboration-Oxidation

Alkenes react with diborane followed by oxidation with hydrogen peroxide/hydroxide to form alcohols.

Wacker Process

Alkenes are directly oxidized to aldehydes or ketones by PdCl₂-CuCl₂ in the presence of air or oxygen.

Tischenko Reaction

Aldehydes undergo simultaneous oxidation and reduction in the presence of aluminium ethoxide to form an ester.

Ozonolysis

Alkenes are oxidized by ozone to form an unstable ozonide, which reduces to aldehydes or ketones depending on the structure.

4. Synthesis and Coupling Reactions

Wurtz Reaction

Alkyl halides react with sodium in dry ether to form alkanes.

Wurtz-Fittig Reaction

A mixture of aryl halide and alkyl halide reacts with sodium to form substituted arenes.

Frankland Reaction

Similar to the Wurtz reaction, but uses Zinc instead of Sodium to react with alkyl halides to form alkanes.

Finkelstein Reaction

Alkyl chlorides or bromides are treated with sodium iodide in acetone to prepare iodoalkanes.

Friedel-Crafts Reaction

Aromatic hydrocarbons react with alkyl halides in the presence of a Lewis acid (like AlCl₃) to form substituted hydrocarbons.

Sandmeyer’s Reaction

Diazonium salts react with CuCl/HCl or CuBr/HBr to form aryl halides.

Gattermann-Koch Reaction

Benzene reacts with CO and HCl in the presence of AlCl₃ to form benzaldehyde.

Kolbe’s Electrolytic Method

Electrolysis of carboxylic acid salts yields higher alkanes.

Corey-House Synthesis

An alkyl halide is converted to lithium dialkyl cuprate and then reacted with another alkyl halide to give an alkane.

Ullmann Reaction

Aryl iodides react with copper metal to yield biphenyls .

Williamson’s Synthesis

Metal alkoxides react with alkyl halides to yield ethers .

Gabriel Phthalimide Synthesis

Phthalimide is converted to N-alkyl phthalimide, which is then hydrolysed to yield primary amines .

Reimer-Tiemann Reaction

Phenol reacts with chloroform and alkali to yield salicylaldehyde.

Oxo Process

Alkenes are heated with water gas (CO + H₂) and a cobalt catalyst to yield aldehydes.

Wohler’s Reaction

Calcium carbide reacts with water to prepare acetylene .

5. Rearrangement and Elimination Reactions

Beckmann Rearrangement

Oximes rearrange in the presence of acid catalysts to form substituted amides.

Hofmann-Bromamide Reaction

Primary amides react with bromine and alkali to yield primary amines with one less carbon atom .

Curtius Rearrangement

Acyl azides allow for the formation of primary amines via an isocyanate intermediate.

Fries Rearrangement

Phenyl esters heated with anhydrous AlCl₃ rearrange to form ortho- or para-hydroxyketones .

Cope Elimination

Tertiary amine oxides containing a β-hydrogen form an alkene upon heating.

Schmidt’s Reaction

Carboxylic acids react with hydrazoic acid (HN₃) to produce primary amines.

6. Halogenation and Other Specific Reactions

Haloform Reaction

Methyl ketones oxidize with sodium hypohalite to yield haloform and a carboxylic acid salt .

Hell-Volhard-Zelinsky (HVZ) Reaction

Carboxylic acids react with bromine/chlorine and red phosphorus to produce α-haloacids.

Hunsdiecker Reaction

Silver salts of carboxylic acids react with bromine to yield alkyl bromides with one less carbon atom.

Balz-Schiemann’s Reaction

Benzene diazonium salt is converted to fluorobenzene via tetrafluoroborate.

Carbylamine Reaction

Primary amines are heated with chloroform and alcoholic KOH to form foul-smelling isocyanides.

Hofmann Mustard Oil Reaction

A test for primary amines where the reaction yields alkyl isothiocyanates which smell like mustard oil.

Schotten-Baumann Reaction

The benzoylation of alcohols or phenols in the presence of NaOH.

Diels-Alder Reaction

A conjugated diene adds to a dienophile to form a cyclic system.

Leuckart Reaction

Aldehydes or ketones undergo reductive amination with ammonium formate to yield primary amines.