Write Short Note:-
(1) Wurtz Reaction
(2) Fittig Reaction
(3) Clemmensen Reduction
(4) Claisen Condensation
Answers
Answer:
Explanation:
Answer:
1. Sandmeyer Reaction
When a primary aromatic amine is treated with sodium nitrite in the presence of cold aqueous mineral acid, a diazonium salt is formed. This freshly prepared diazonium salt is further mixed with cuprous chloride or bromide which results in the replacement of diazonium group by –Cl or –Br. This reaction for the synthesis of haloarenes from a diazonium salt is popularly known as Sandmeyer reaction.
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2. Gattermann Reaction
The Gattermann reaction, (also known as the Gattermann salicylaldehyde synthesis) is a chemical reaction in which aromatic compounds are formylated by hydrogen cyanide in the presence of a Friedel–Crafts catalyst (e.g. AlCl3). It is named for the German chemist Ludwig Gattermann and is similar to the Friedel-Crafts reaction.
3. Balz-Schiemann Reaction
The conversion of aryl amines to aryl fluorides via diazotisation and subsequent thermal decomposition of the derived tetrafluoroborates or hexafluorophosphates. The decomposition may also be induced photochemically.
4. Finkelstein Reaction
Treatment of a primary alkyl halide or pseudohalide with an alkali metal halide (e.g. KF, KI) leads to replacement of the halogen via an SN2 Reaction. This is really very important for JEE Mains and Advanced Exam.
5. Swartz Reaction
Swarts reaction and Finkelstein reactions are halogen exchange reactions that are associated with alkyl halides.
Swarts reaction: RX + MF → RF+ MX
6. Wurtz Reaction
The Wurtz reaction, named after Charles-Adolphe Wurtz, is a coupling reaction in organic chemistry, organometallic chemistry and recently inorganic main group polymers, whereby two alkyl halides are reacted with sodium to form a new alkane:
2R–X + 2Na → R–R + 2Na+X. −
7. Fitting Reaction
In Fittig reaction, two aryl halides are coupled in presence of sodium metal in dry ether or tetrahydrofuran to furnish biaryls.
8. Wurtz – Fittig Reaction
The Wurtz–Fittig reaction is the chemical reaction of aryl halides with alkyl halides and sodium metal in the presence of dry ether to give substituted aromatic compounds.
9. Kolbe’s Reaction
10. Reimer- Tiemann Reaction
The Reimer–Tiemann reaction is a chemical reaction used for the ortho-formylation of phenols; with the simplest example being the conversion of phenol to salicylaldehyde. The reaction was discovered by Karl Reimer and Ferdinand Tiemann.
11. Rosenmund Reduction
The reaction is catalysed by palladium on barium sulfate, which is sometimes called the Rosenmund catalyst. Barium sulfate has a low surface area which reduces the activity of the palladium, preventing over-reduction. However, for certain reactive acyl chlorides the activity must be reduced further, by the addition of a poison.
12. Gattermann – Koch Reaction
The Gattermann–Koch reaction, named after the German chemists Ludwig Gattermann and Julius Arnold Koch, refers to a Friedel–Crafts acylation reaction in which carbon monoxide, hydrochloric acid, and a Friedel–Crafts catalyst (e.g. AlCl3) are used to produce aromatic aldehydes from various aromatic compounds, including derivatives of benzene and naphthalene:
13. Stephen Reaction or Stephen Reduction
14. Clemmensen Reduction
Clemmensen reduction is a chemical reaction described as a reduction of ketones (or aldehydes) to alkanes using zinc amalgam and hydrochloric acid. This reaction is named after Erik Christian Clemmensen, a Danish chemist.
15. Wolff – Kishner Reduction
16. Haloform Reaction (Iodoform Reaction)
17. Aldol Condensation
18. Cannizzaro Reaction
19. Friedel – Crafts Reaction
20. Grignard Synthesis
21. Esterification Reaction or Fischer Esterification
22. Williamson Synthesis
23. Diazotisation Reaction
Explanation: