Explain HVZ reaction with equations.

The reaction conditions for the Hell Volhard Zelinsky reaction are quite severe- involving reaction temperatures above 373 K and increased reaction time. The reaction usually requires less than one equivalent of phosphorous (or a trihalide of phosphorous). Some carboxylic acids and acid derivatives such as acyl halides or anhydrides can be halogenated in the absence of a catalyst. This reaction is known as HVZ reaction.

Explain Williamson's ether synthesis with equations.

Williamson synthesis is used for the preparation of simple as well as mixed ethers. Alkyl halide is heated with alcoholic sodium or potassium alkoxide to form corresponding ethers. R − ONa + X − R ' → Δ R − O − R ' + NaX . Thus, methyl iodide, on heating with alcoholic sodium methoxide forms dimethyl ether. CH 3 − ONa + I − CH 3 → Δ CH 3 − O − CH 3 + NaI .

Explain Riemer - Tiemann reaction with equations.

The Reimer Tiemann reaction is an organic chemical reaction where phenol is converted into an ortho hydroxy benzaldehyde using chloroform, a base, and acid workup. This results in a nucleophilic attack on the dichlorocarbene, forming an intermediate dichloromethyl substituted phenol.

Explain Kolbe's reaction with equations.

When phenol is treated with sodium hydroxide, sodium phenoxide is produced. This sodium phenoxide when treated with carbon dioxide, followed by acidification, undergoes electrophilic substitution to give ortho-hydroxybenzoic acid as the main product. This reaction is known as Kolbe's reaction.

Describe the following: Decarboxylation

Decarboxylation: Decarboxylation refers to the reaction in which carboxylic acids lose carbon dioxide to form hydrocarbons when their sodium salts are heated with soda lime. Example: CH 3 COONa → △ NaOH and CaO CH 4 + Na 2 CO 3 Decarboxylation also takes place when aqueous solutions of alkali metal salts of carboxylic acids are electrolysed. This electrolytic process is known as Kolbe's electrolysis.