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Question
Arrange the following compounds in increasing order of reactivity towards SN2 reaction.
2-Bromopentane, 1-Bromopentane, 2-Bromo-2-methylbutane
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Solution
SN2 reaction involves the formation of transition state. Therefore, reactivity towards SN2 depends upon the steric hindrance:
Due to the presence of 2 methyl group in 2-Bromo-2-methylbutane it is least reactive towards SN2 reactions, 2-bromopentane is moderately reactive while 1-bromopentane is most reactive.
2-Bromo-2-methylbutane < 2-Bromopentane < 1-Bromopentane
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