Name reactions are chemical reactions that are recognized by a specific name. Name reactions are usually named after the person who discovered or developed it. Hundreds of well known organic reactions have been named after people who discovered it. But name reactions are not always named after their discoverers. Some reactions are named on the basis of the key reactants used, the type of product formed, or the main transformation that happens in the reaction.
30 most important name reactions which are frequently asked in class 12 chemistry exams are listed below:
Contents
- 1. Dehydrohalogenation reaction (Elimination reaction)
- 2. Wurtz reaction
- 3. Fittig reaction
- 4. Wurtz-Fittig reaction
- 5. Carbylamine reaction: Test reaction of primary amines
- 6. Sandmeyer reaction
- 7. Gattermann reaction
- 8. Diazotization reaction
- 9. Dows Process
- 10. Oxo-process (Carbonylation reaction)
- 11. Fermentation
- 12. Esterification reaction
- 13. Kolbe’s reaction (Carboxylation reaction)
- 14. Haloform reaction
- 15. Coupling reaction
- 16. Reimer-Tiemann reaction
- 17. Williamson’s ether synthesis
- 18. Ozonolysis reaction
- 19. Rosenmund reduction
- 20. Clemmensen’s reduction
- 21 . Wolff-Kishner reduction
- 22. Aldol condensation reaction
- 23. Cannizzaro’s reaction
- 24. Perkin’s (condensation) reaction
- 25. Benzoin condensation reaction
- 26. Hell-Volhard Zelinsky [HVZ] reaction
- 27. Claisen condensation reaction
- 28. Hoffmann’s Bromamide reaction: Decarbonylation reaction
- 29. Friedel Craft’s reaction
- 30. Hydroboration-Oxidation of alkene
- Links to get mechanism of some name reactions
1. Dehydrohalogenation reaction (Elimination reaction)
When an alkyl halide is heated with alcoholic solution of KOH, then a molecule of hydrogen halide is eliminated from the haloalkane and alkene is formed. Therefore this reaction is also called dehydrohalogenation reaction. Eg.
Elimination reaction involves the removal of halogen atom of haloalkane and a hydrogen atom from the β- carbon (i.e. adjacent carbon). Therefore, this reaction is also known as β- elimination reaction.
2. Wurtz reaction
When an alkyl halide( haloalkane) is heated with sodium metal in presence of dry ether, a symmetrical alkane containing double number of carbon atoms than in haloalkane is formed. This reaction is called Wurtz reaction.
3. Fittig reaction
Haloarenes when treated with sodium in the presence of dry ether, diaryls are produced. This reaction is known as Fittig reaction.
4. Wurtz-Fittig reaction
Haloarenes when treated with sodium and alkyl halide in presence of dry ether gives toluene. This reaction is known as Wurtz-Fittig reaction.
5. Carbylamine reaction: Test reaction of primary amines
When chloroform is warmed with a primary amine in the presence of alcoholic KOH, an offensive(unpleasant) smell of carbylamines ( i.e. isocyanide) is obtained. This reaction is known as carbylamine reaction.
6. Sandmeyer reaction
Chlorobenzene can be prepared by treating benzene diazonium chloride with cuprous chloride dissolved in HCl. This reaction is called Sandmeyer reaction.
7. Gattermann reaction
Chlorobenzene is prepared by treating benzene diazonium chloride with copper powder dissolved in HCl. This reaction is the modification of Sandmeyer’s reaction and called Gattermann reaction.
8. Diazotization reaction
When aniline is treated with sodium nitrite (NaNO2) and dil.HCl at temperature below 50C, benzene diazonium chloride is obtained. This reaction is known as diazotization reaction.
9. Dows Process
When chlorobenzene is heated with an aqueous solution of NaOH at 3000C and 200 atm gives sodium phenoxide which on acidification gives phenol.
10. Oxo-process (Carbonylation reaction)
Alkenes react with carbon monoxide and hydrogen in the presence of cobalt carbonyl catalyst [Co(CO)4]2 at high pressure and temperature to give aldehyde, which on catalytic hydrogenation gives primary alcohol. Eg.
11. Fermentation
Fermentation is a biochemical process of degradation (slow decomposition/ breaking down) of large organic molecules like sugars and starches into simpler compounds by the catalytic action of enzymes.
Eg. Ethanol from sugar: Enzymes invertase and zymase are obtained from yeast. The reactions occurring during the fermentation of sugar are:
12. Esterification reaction
Alcohols react with carboxylic acids in the presence of few drops of conc. H2SO4 to form esters. This reaction is known as esterification reaction.
13. Kolbe’s reaction (Carboxylation reaction)
Sodium phenoxide when heated with CO2 at1350C under a pressure of 4-7 atm, sodium salicylate is obtained which when acidified gives salicylic acid.
14. Haloform reaction
Aldehydes and ketones containing CH3CO- group on reaction with excess halogen in presence of NaOH gives haloform (chloroform’ bromoform, iodoform). Eg.
15. Coupling reaction
Phenol or aniline reacts with benzene diazonium chloride in slightly alkaline medium and at low temperature to form coloured compounds called azo dyes. This reaction is called coupling reaction.
16. Reimer-Tiemann reaction
When phenol is refluxed with chloroform and aq. NaOH at 600C, a mixture of o-hydroxybenzaldehyde and p-hydroxybenzaldehyde is obtained. This reaction is called Reimer-Tiemann reaction.
17. Williamson’s ether synthesis
The reaction in which alkyl halide and sodium or potassium alkoxide are reacted to form ether is known as Williamson’s etherification reaction. Eg.
Both symmetrical and unsymmetrical ether can be prepared from this reaction. Eg.
18. Ozonolysis reaction
Alkene reacts with ozone to give ozonide. On warming ozonide with Zn in water, it breaks down to give two molecules of carbonyl compounds (aldehyde or ketone). This process of formation of ozonide and it’s decomposition to give carbonyl compounds is called ozonolysis.
19. Rosenmund reduction
Aldehydes can be prepared by reducing acid chloride solution with hydrogen in the presence of Palladium(Pd) catalyst deposited on barium sulphate and partially poisoned with sulphur or quinoline. This reaction is called Rosenmund reduction.
20. Clemmensen’s reduction
The reduction of aldehydes and ketones to alkane using zinc amalgam and conc. HCl is Clemmensen’s reduction. In this reaction, carbonyl group (-CO-) is reduced to -CH2– group. Eg.
21 . Wolff-Kishner reduction
In this method aldehyde and ketone is treated with hydrazine to form hydrazone which is then heated with KOH in presence of glycol to give alkane. Eg.
22. Aldol condensation reaction
Condensation between two molecules of aldehydes or ketones having at least one α – hydrogen atom in presence of dilute alkali to form β-hydroxy aldehyde or β-hydroxy ketone is known as aldol condensation reaction. Examples:
Aldehydes and ketones which do not contain any α – hydrogen atom such as HCHO, (CH3)3CCHO, C6H5CHO, etc. do not undergo aldol condensation reaction.
23. Cannizzaro’s reaction
Aldehydes which do not contain α-hydrogen like HCHO, C6H5CHO,etc. undergo self oxidation and reduction on treatment with conc. alkali. In this reaction one molecule is oxidized to carboxylic acid and other molecule is reduced to alcohol. Thus, a mixture of an alcohol and a salt of carboxylic acid is formed by Cannizzaro’s reaction
24. Perkin’s (condensation) reaction
The condensation of an aromatic aldehyde with an acid anhydride in the presence of sodium or potassium salt of the same acid to produce α,β-unsaturated acid is known as the Perkin’s condensation.
25. Benzoin condensation reaction
Benzaldehyde when heated with alcoholic solution of potassium cyanide, undergoes self condensation between two molecules to form an α-hydroxy ketone known as benzoin. This reaction is called benzoin condensation reaction. Eg.
26. Hell-Volhard Zelinsky [HVZ] reaction
Carboxylic acids (except formic acid) reacts with chlorine or bromine in presence of red phosphorous to give α-chloro or α-bromo acids. The reaction does not stop at monosubstituted product but continues till all α-hydrogen atoms are replaced.
![Hell-Volhard Zelinsky [HVZ] reaction](https://chemicalnote.com/wp-content/uploads/2025/02/https-chemicalnote-com-wp-content-uploads-2022-0-4.png)
27. Claisen condensation reaction
Condensation between two molecules of esters having α-hydrogen atom in the presence of strong base like sodium ethoxide and an acid to form β-keto ester is known as Claisen condensation reaction. Eg.
28. Hoffmann’s Bromamide reaction: Decarbonylation reaction
When an amide is treated with bromine in NaOH or KOH, carbonyl group is removed from made to form primary amine containing one carbon less than that of amide. This reaction is known as Hoffmann bromamide reaction or decarbonylation reaction.
29. Friedel Craft’s reaction
a. Friedel Craft’s alkylation reaction: Introduction of an alkyl group ( – R ) in the benzene ring by treating benzene with an alkyl halide in the presence of anhydrous AlCl3 is known as Friedel- Craft’s alkylation reaction.
b. Friedel craft’s acylation reaction : Introduction of an acyl group (i.e.keto group) in the benzene ring by treating benzene with acid chloride or acid anhydride in the presence of anhydrous AlCl3 is known as Friedel- Craft’s acylation reaction.
30. Hydroboration-Oxidation of alkene
In this method, alkene is treated with diborane, (BH3)2 or B2H6 followed by alkaline oxidation with H2O2 to get primary alcohol.
Hydroboration is a reduction process, which is carried out by treating with diborane, (BH3)2 to give trialkyl borane, which upon oxidation with alkaline solution of H2O2 gives primary alcohol. For example:
Links to get mechanism of some name reactions
- https://chemicalnote.com/aldol-condensation-and-crossed-aldol-condensation-reaction-definition-examples-mechanism-and-uses/
- https://chemicalnote.com/cannizzaros-reaction-and-crossed-cannizzaros-reaction-definition-examples-and-mechanism/
- https://chemicalnote.com/claisen-condensation-reaction-examples-and-mechanism/
- https://chemicalnote.com/diazotization-reaction-mechanism-and-uses/
- https://chemicalnote.com/witting-reaction-examples-and-mechanism/
- https://chemicalnote.com/acetoacetic-ester-synthesis-of-ketones/
- https://chemicalnote.com/malonic-ester-synthesis-of-carboxylic-acids/
