An SN1 reaction is a two-step reaction that only depends on one species for its rate. The two steps of an SN1 reaction are a carbocation formation and a nucleophilic attack. The carbocation forms due to the leaving group departing and the rate of the reaction is dependent on the stability of the carbocation. A high carbocation substitution indicates a more stable carbocation. Therefore, an SN1 reaction favors a tertiary carbocation. The polar protic solvents of an SN1 reaction tend to be the nucleophile that attacks the carbocation. The SN1 reaction scheme and mechanism of 2-chloro-2-methylbutane from 2-methyl-2-butanol is indicated in Figure 1 shown below.
