Sn1 Reaction Lab Report

Introduction

An unimolecular substitution reaction, SN1 reaction, has a two step mechanism that results in a halide group being displaced by a nucleophile1. In an SN1 reaction, the first step involves the leaving of a halide group to form a carbocation intermediate. This is the rate determining step, and it is also the slowest step. In the second step a nucleophile attacks a face of the the carbocation. Figure 1 displays this mechanism. Only one molecule, the substrate, determines the rate determining step in an SN1 reaction. The nucleophile has no relevance to the rate law in this reaction. The structure of the substrate play a key role in SN1 reaction. Since SN1 reaction form a carbocation intermediate, the reaction will prefer molecules

Since bromine is bigger than chlorine is can hold a charge better and be content by itself. This also means that a bromine leaving group would result in a weaker base.

In the reaction of 1-chlorobutane with cyanide ion, the reaction rate is increased by the addition of a catalytic amount of sodium iodide. Explain this result.

This is the result because The iodide displaces the chlorine forming 1-iodobutane. Since iodine is a much better leaving group than chlorine,
1-iodobutane will allow the cyanide ion to displace the leaving group much easier. The sodium ions will then ionically bond with the iodide ions to reform sodium iodide. This process lowers the total activation energy for the reaction. What would be the major product if 1,4-dibromo-4-methylpentane was allowed to react with one equivalent of NaI in Acetone? The major product would be 4-bromo-1-iodo-4-methylpentane. one equivalent of silver nitrate in ethanol? The major product would be