Page 219 - Chemical and process design handbook

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CHLORAL

Chloroacetaldehydes are produced by the reaction of acetaldehyde with
chlorine by replacement of the hydrogen atoms of the methyl group.
Chlorine reacts with acetaldehyde at room temperature to give mono-
o
chloroacetaldehyde. Increasing the temperature to 70 to 80 C gives dichlor-
o
oacetaldehyde, and at a temperature of 80 to 90 C trichloroacetadehyde,
(chloral) is formed.
CH CH=O + Cl → CH ClCH=O + HCl
3 2 2
CH ClCH=O + Cl → CHCl CH=O + HCl
2 2 2
CHCl CH=O + Cl → CCl CH=O + HCl
2 2 3
Bromal is formed by an analogous series of reactions.

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