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Chemistry halogenoalkanes a-level question

Hi!! Really confused with this question, any chance I could have some help?

When 3-bromo-2,3-dimethylpentane reacts with ethanolic sodium hydroxide, three structurally isomeric alkenes are formed.
a) Write the structures and names of the alkenes produced.
b) Bromoethane also reacts with ethanolic sodium hydroxide to form ethene. Suggest one reason why this method for making ethene is not used in industry.

Any help would be much appreciated!! :smile:
Reply 1
a) The halogenoalkane performs elimination due to the reaction with NaOH in alcoholic conditions. The C=C bond can form on any side of the bromine (including the adjacent methyl group) so 2,3-dimethylpent-2-ene, 2,3-dimethylpent-3-ene and 2-ethyl-3-methylbut-1-ene are formed.

b) I'm not sure about this one, but maybe something about it being cheaper to use cracking of long chain hydrocarbons?
Reply 2
Original post by George H.
a) The halogenoalkane performs elimination due to the reaction with NaOH in alcoholic conditions. The C=C bond can form on any side of the bromine (including the adjacent methyl group) so 2,3-dimethylpent-2-ene, 2,3-dimethylpent-3-ene and 2-ethyl-3-methylbut-1-ene are formed.

b) I'm not sure about this one, but maybe something about it being cheaper to use cracking of long chain hydrocarbons?

Okay that makes a lot more sense, thank you so much!

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