# Write the reaction equations of (i)2-bromo-2-methylpropane + magnesium in dry ether; (ii)product of (i) + water?

Aug 27, 2015

This is the preparation and hydrolysis of a Grignard reagent.

#### Explanation:

Part (i)

This is the preparation of a Grignard reagent.

"R-X" + "Mg" stackrelcolor (blue)("dry ether")(→) underbrace("R-MgX")_("Grignard Reagent")

("CH"_3)_3"C-Br" + "Mg" stackrelcolor (blue)("dry ether")(→) ("CH"_3)_3"C-MgBr"

Part (ii)

This is the hydrolysis of a Grignard reagent.

$\text{R-MgX" + "H"_2"O" → "RH" + "MgX(OH)}$

The $\text{R-MgX}$ behaves as if it were $\text{R"^- ,""^+"MgX}$.

The ${\text{R}}^{-}$ is a strong base, so it removes a proton from the water to form $\text{RH}$.

$\text{(CH"_3)_3"C-MgBr" + "H"_2"O" → "(CH"_3)_3"C-H" + "MgBr(OH)}$
Note: the $\text{MgBr(OH)}$ is a gelatinous substance, so the hydrolysis is usually carried out in the presence of dilute acid to dissolve the basic salt.