SN2 - Reaction Energy Diagram

This interactive diagram shows the Potential Energy Surface (PES) for the S_N2 reaction of propyl bromide with the conjugate base of ethyl thiol. Hover over the structures, arrows, or points on the graph to learn more about each stage of the reaction. Consider the questions posed as you explore.

1. SN2 Reaction: Propyl Bromide + Conjugate Base of Ethyl Thiol
   • Hover over propyl bromide: "This is our starting material, propyl bromide. Consider: What makes the carbon bonded to the bromine electrophilic?"
   • Hover over the conjugate base of ethyl thiol (i.e. the thiolate ion): "This is our nucleophile, the conjugate base of ethyl thiol. Consider: Why is this a good nucleophile? What is the significance of the negative charge?"
   • Hover over the transition state: "This transition state represents the concerted attack of the nucleophile and departure of the leaving group. Consider: What is happening to the bonds in this transition state? Is the reaction concerted or stepwise? What does 'concerted' mean?"
   • Hover over the product: "This is our final product. Consider: What is the stereochemical outcome of this SN2 reaction? Is there inversion of configuration? Why or why not? Compare the energy of the starting material and the product. Is this reaction endothermic or exothermic?"
   • Hover over the leaving group (Br⁻): "Bromide ion, the leaving group. Consider: Why is bromide a good leaving group?"