Industrial synthesis allyl chloride

Allyl chloride is quite reactive toward nucleophilic substitutions, especially those that proceed by the Sn2 mechanism, and is used as a starting material in the synthesis of a variety of drugs and agricultural and industrial chemicals. 

In the reaction example of Figure 1.22, the industrial synthesis of allyl chloride, only an H atom in the allylic position is substituted. Its precursor is a resonance-stabilized (Table 1.1, center line) allylic radical. 

Allylic chlorinations are important in industry because chlorine is relatively cheap. For example, 3-chloropropene (allyl chloride) is made commercially by the gas-phase chlorination of propene at 400°C. It is a building block for the synthesis of epoxy resin and many other useful substances. 

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