Why is there a difference in mechanism between tertiary halogenoalkanes and primary halogenoalkanes in nucleophilic substitution?

The difference in mechanism between tertiary halogenoalkanes and primary halogenoalkanes is caused by the difference in relative stability between the two carbocation intermediates formed. In the case of tertiary halogenoalkanes which have methyl groups attached to the functional group carbon, the methyl groups are able to stabilise the positive charged formed upon nucleophilic attack on the functional group carbon, making the intermediate more stable. This is not seen in primary halogenoalkanes, where the inductive stabilising effect of the functional group carbon is only caused by one methyl group as opposed to three. This is why tertiary halogenoalkanes follow Sn1, and primary halogenoalkanes follow Sn2.

NO
Answered by Nketia O. Chemistry tutor

14059 Views

See similar Chemistry A Level tutors

Related Chemistry A Level answers

All answers ▸

How do you describe the process of recrystallisation to purify a product?


Calculate Gibbs free energy when S = 131 J mol-1 and H = 155 kJ mol-1 at 25 C, stating whether or not the reaction is feasable.


Deduce which of Na+ and Mg2+ is the smaller ion. Explain your answer.


Explain why first ionisation energy decreases down a group.


We're here to help

contact us iconContact ustelephone icon+44 (0) 203 773 6020
Facebook logoInstagram logoLinkedIn logo

MyTutor is part of the IXL family of brands:

© 2025 by IXL Learning