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Can methyl oxirane(epoxide) (a mono substituted 3 membered cyclic ether) form alcohols by reacting it with Grignard reagent? If yes, can you please explain the reaction with mechanism? If no, why?

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    $\begingroup$ ``Ethers react with Grignard reagent to form alcohols```- where did you get this from? Grignards are usually prepared in ether solvents. They do not react with them. $\endgroup$ – bon May 27 '16 at 16:34
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    $\begingroup$ Grignard Reagents only react with three-member cyclic ethers (epoxides). As bon says, they don't react with any other kind of ether. $\endgroup$ – Lighthart May 27 '16 at 16:39
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    $\begingroup$ Technically, they react with oxetanes as well: chemistry.stackexchange.com/questions/21921/… but that's hardly the point :) $\endgroup$ – orthocresol May 27 '16 at 16:55
  • $\begingroup$ Sorry. I have edited the question. Please forgive me $\endgroup$ – sai saandeep May 27 '16 at 17:03
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Yes, Girgnard reagents can act as nucleophiles in the ring opening of epoxides. Nucleophilic attack occurs much faster at the less hindered carbon, so the product of this reaction will predominate. The reaction results in the formation of an alkoxide, and does not form the alcohol until treated with a protic acid. The mechanism for Grignard addition to epoxypropane (methyl oxirane) is:

$\hspace{4cm}$epoxypropane grignard

For 2-methyl-2,3-epoxybutane, a more hindered epoxide, the addition still occurs at the less hindered carbon:

$\hspace{3.8cm}$2-methyl-2,3-epoxybutane

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