Give three methods of preparation of anisole.

Answer

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Hint: At first think about the chemical formula and structure of anisole. Anisole is a mono methoxy benzene that is benzene substituted by a methoxy group. It has a role as a plant metabolite. It is an ether.

Complete step by step answer:
Anisole or methoxy benzene is an organic compound with the formula

C H_{3} O C_{6} H_{5}

. It is an aromatic ether. It undergoes electrophilic aromatic substitution reaction more quickly than benzene.
Anisole can be prepared from the following methods
1.Williamson’s synthesis

C_{6} H_{5} - O N a + B r - C H_{3} \to C_{6} H_{5} - O C H_{3} + N a B r

2.By methylation of sodium phenoxide with dimethyl sulphate or methyl chloride

2 C_{6} H_{5} - O N a \to_{- N a_{2} S O_{4}}^{{(C H_{3} O)}_{2} S O_{2}} 2 C_{6} H_{5} - O C H_{3}

3.Using diazomethane

C_{6} H_{5} - O H + C H_{2} = N = N \overset{B F_{3}}{\to} C_{6} H_{5} - O C H_{3}

Additional information:
It is a colorless liquid with a smell reminiscent of anise seed, and in fact many of its derivatives are found in natural and artificial fragrances. It is a precursor to other synthetic compounds. Anisole undergoes electrophilic aromatic substitution reaction more quickly more than benzene does, when in turn reacts more quickly than nitrobenzene. The methoxy group is an ortho/para directing group, which means that the electrophilic substitution reaction preferentially occurs at these three sites. The enhanced nucleophilicity of anisole vs benzene reflects the influence of the methoxy group, which renders the ring more electron-rich. Anisole is a precursor to perfumes, insect pheromones and pharmaceuticals. Its main hazard is its flammability.

Note:
Don’t get confused with the terms anisole and aniline. Aniline is the simplest aromatic amine in which the benzene ring is attached to the amino group whereas anisole is an ether in which the benzene ring is attached to the methoxy group.