Question

Construct a three-step synthesis of 3-bromo-3-methyl-2-butanol from 2-methyl-2-butene by dragging the appropriate formulas into the bins. Note that each bin will hold only one item, and not all of the given reagents or structures will be used.

Answer 1

Answer:

See explanation

Explanation:

In order to do this, we need to use 3 reagents to get the final product.

The first one, and logic is the halogenation of the alkene. Doing this, with Br2/CCl4, we'll get an alkane with two bromines, one in carbon 2 and the other in carbon 3.

Then, the next step is to eliminate one bromine of the reactant. The best way to do this, is using sodium ethoxide in ethanol. This is because sodium ethoxide is a relatively strong base, and it will promove the product of elimination in major proportions rather than the sustitution product. If we use NaOH is a really strong base, and it will form another product.

When the sodium ethoxide react, it will form a double bond between carbon 1 and 2 (The carbon where one bromine was with the methyl, changes priority and it's now carbon 3).

The final step, is now use acid medium, such H3O+/H2O or H2SO4/H2O. You can use any of them. This will form an carbocation in carbon 2 (it's a secondary carbocation, so it's more stable that in carbon 1), and then, the water molecule will add to this carbon to form the alcohol.

See the attached picture for the mechanism of this.