How does sn2 affect stereochemistry

Frontside Attack: In a frontside attack, the nucleophile attacks the electrophilic center on the same side as the leaving group. When a frontside attack occurs, the stereochemistry of the product remains the same; that is, we have retention of configuration. Backside Attack: In a backside attack, the nucleophile attacks the electrophilic center on the side that is opposite to the leaving group. When a backside attack occurs, the stereochemistry of the product does not stay the same.

There is inversion of configuration. Experimental Observation: Al l S N 2 Re actions Proceed With Nucleophilic Backside Attacks Experimental observation shows that all S N 2 reactions proceed with inversion of configuration; that is, the nucleophile will always attack from the backside in all S N 2 reactions.

Ingold J. Aliphatic substitution and the Walden inversion. Part I E. Hughes, F. Juliusburger, S. Masterman, B. Topley, and J. Weiss J. Part XLII. Introductory remarks, and kinetics of the interaction of chloride ions with simple alkyl chlorides in acetone B. Part XXVI. Section A introductory remarks, and a kinetic study of the reactions of methyl, ethyl, n-propyl, isobutyl, and neopentyl bromides with sodium ethoxide in dry ethyl alcohol I.

Dostrovsky and E. Hughes J. This can be attributed to sterics, as backside attack of the substituted carbon becomes increasingly challenging. Bicyclic Structures Prohibiting the Walden Inversion.

Bartlett and Edward S. In the first paragraph, Prof. Conversely, if the trans configuration is the substrate, the resulting product will be cis. Predict the product of a nucleophilic substitution of S bromopentane reacting with CH 3 CO 2 - , Show stereochemistry.

Learning Objective predict the products and specify the reagents for S N 2reactions with stereochemistry propose mechanisms for S N 2 reactions draw and interpret Reaction Energy Diagrams for S N 2reactions. Frontside Orientation: In a frontside orientation, the nucleophile approaches the electrophilic center on the same side as the leaving group.

With frontside orientation, the stereochemistry of the product remains the same; that is, we have retention of configuration. Backside Orientation: In a backside orientation, the nucleophile approachss the electrophilic center on the side that is opposite to the leaving group.

The rate law indicates which molecules are in the transition state, but it does not specify how they come together. This can be accomplished by attacking a stereocenter: R 1 , R 2 and R 3 represent three different groups.

LG is a good Leaving Group. The nucleophile can attack the stereocenter in two ways. In frontside attack, it attacks from the same side as the leaving group. In backside attack, it attacks from the opposite side of the leaving group. These two modes of attack give retenti on and inversion of stereochemical configuration, respectively.