Reactions of Epoxides with Anionic Nucleophiles

The most striking chemical property of epoxides is their far greater reactivity toward nucleophilic reagents compared with simple ethers. They react rapidly and exothermically with anionic nucleophiles to yield ring-opened products. This enhanced reactivity results from the angle strain of epoxides ring-opening relieves that strain. 

We saw an example of nucleophilic ring opening of epoxides in Section 15.4, where the reaction of Grignard and organolithium reagents with ethylene oxide was presented as a synthetic route to primary alcohols  

Typical anionic nucleophiles react with epoxides in water or alcohols as the solvent to give an aUcoxide intermediate that is rapidly converted to an alcohol by proton transfer. 

What is the principal organic product formed in the reaction of ethylene oxide with each of the following  

The reactions of epoxides with anionic nucleophiles have many of the characteristics of Sn2 reactions. Inversion of configuration occurs at the carbon attacked by the nucleophile  

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