A few reflections on the material from Monday morning’s lecture.
Epoxide ring-opening. First, epoxides can react with strong nucleophiles without adding acid. The strained ring makes the epoxide reactive. These reactions look like SN2 reactions.
Second, epoxides can react with much weaker nucleophiles by adding acid. Examples of weak nucleophiles include water, alcohols, carboxylic acids. The mechanisms of these reactions are a little strange. If one epoxide carbon is tertiary, the nucleophile adds there, but regardless of where the nucleophile adds, a backside attack occurs. So a little SN1 and a little SN2-like behavior all at the same time.
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