Grignard reactions dibromoethane

Add 2-chloromethyl-2-propenyl benzyl ether3,42 (0.49 g, 2.5 mmol) and 1,2-dibromoethane (0.094 g, 0.5 mmol), and regulate the reaction temperature so as to induce and maintain a smooth reaction of the chloride with magnesium producing the desired Grignard reagent (about 90% yield). 

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