Answer to Question #225535 in Inorganic Chemistry for Simal Kumar Mandi

Question

How will you prepare isopropanol and acetic acid from CH3MgBr?

Answer 1

You dump dry ice (CO2) into it, let it react a while, and then add some acid to neutralize the magnesium bromo acetate (CH3-COOMgBr). The reaction is

CH3MgBr + CO2 → CH3-COOMgBr

CH3-COOMgBr + H+ → CH3-COOH

The product is acetic acid (CH3-COOH) though this is a very expensive way to make acetic acid. A pound (454 g) of methyl bromide (which you need to make the CH3MgBr from) will cost you $460. Even with 100% yield, you will only get about 0.63 lb (287 g) of acetic acid. A pound of acetic acid costs less than $20. Then add in what the Mg, acid, CO2 will cost you makes making it this way even more expensive.