Which alkyl halide would you expect to undergo an SN2 reaction most slowly?
1-bromo-4-methylpentane
1-bromo-3-methylpentane
1-bromo-2-methylpentane
1-bromo-2,2-dimethylbutane
I am really confused with this topic and no I have been reading up on it, but I do not know how to approach such a question
1-bromohexane
Actually I just read something up on how it depends on the nature of the carbon atom as in if it is a primary carbon or tertiary?
With tertiary forming a more stable carbocation
To determine which alkyl halide would undergo an SN2 reaction most slowly, you need to consider the factors that influence the reactivity of SN2 reactions. These factors include sterics, the nature of the alkyl group, and the stability of the leaving group.
In an SN2 reaction, the nucleophile attacks the substrate from the backside, leading to a concerted reaction where the bond between the nucleophile and the substrate forms as the leaving group departs. Therefore, the reactivity of the substrate largely depends on how accessible the backside of the molecule is to the nucleophile.
In this case, all the alkyl halides mentioned are primary alkyl halides except for 1-bromo-2,2-dimethylbutane, which is a tertiary alkyl halide. Tertiary alkyl halides are unreactive in SN2 reactions due to steric hindrance. The bulky alkyl groups around the reactive carbon make it difficult for the nucleophile to approach the carbon from the backside, thus slowing down the reaction rate.
So, given the options, 1-bromo-2,2-dimethylbutane is the alkyl halide that would undergo an SN2 reaction most slowly.
Remember, it's important to consider the factors mentioned above, such as sterics and the nature of the alkyl group, to determine the reactivity of alkyl halides in SN2 reactions.