Grignard reagents react with oxirane (ethylene oxide)to form 1 $\circ$ alcohols but can be prepared in tetrahydrofuran solvent.Why is this difference in behavior observed?

Question

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The difference in behavior observed is due to the higher strain energy present in the oxirane ring. This makes it more reactive towards nucleophiles like Grignard reagents, resulting in the formation of 1° alcohols. In contrast, tetrahydrofuran is a less strained cyclic ether and is a better solvent for Grignard reactions. Steric hindrance (choice A) is unlikely to be the cause of the observed difference in behavior. The leaving group in both cases is the same (choice B) and the presence of water can be eliminated by careful drying of the reagents, so choice D is also incorrect. Finally, while oxirane is a cyclic ether and tetrahydrofuran is a hydrocarbon (choice E), this difference alone does not explain the observed difference in reactivity.

Grignard Reagents React with Oxirane (Ethylene Oxide)to Form 1 ∘\circ∘ Alcohols but Can Be Prepared in Tetrahydrofuran Solvent

Grignard Reagents React with Oxirane (Ethylene Oxide)to Form 1^$\circ$ Alcohols but Can Be Prepared in Tetrahydrofuran Solvent