SolutionsReactivity
1. Solvents
Why are diethyl ether and THF good solvents for Grignard reagents?
Because they are unreactive (they have no acidic hydrogens or good leaving groups) and the lone pairs of the oxygen coordinate to magnesium and stabilize the reagent.
2. Ethers and epoxides
Why does hydroxide not cleave diethyl ether but open ethylene oxide?
In the ether, the leaving group would be an alkoxide, a very bad leaving group. In the epoxide, the high ring strain makes up for that difficulty and ring opening is favourable.