Question

Draw a structural formula of an alkene or alkenes (if more than one) that undergo acid-catalyzed hydration and without rearrangement give 2-methyl-2-butanol as the MAJOR product. You do not have to consider stereochemistry. You do not have to explicitly draw H atoms. If more than one structure fits the description, draw them all. Draw one structure per sketcher. Add additional sketchers using the drop-down menu in the bottom right corner. Separate structures with signs from the drop-down menu.

Answer 1

Answer:

-) 2-methylbut-2-ene

-) 2-methylbut-1-ene

-) 3-methylbut-1-ene

Explanation:

in this case, the hydration of alkenes is a marknovnikov reaction, this means that the "OH" group would be added in the most substituted carbon of the double bond. (Figure 1)

For 2-methylbut-2-ene the most substituted carbon is the tertiary carbon (the carbon in the right of the double bond), so we will obtain the desired molecule. In 2-methylbut-1-ene the most substituted carbon is again the tertiary carbon (the carbon in the bottom of the double bond), so we will obtain 2-methyl-2-butanol. Finally, for 3-methylbut-1-ene the carbocation would be formed on carbon 3, this is a secondary carbocation. We can obtain a most stable carbocation if we do a hydride shift (Figure 2). With this new molecule is possible to obtain 3-methylbut-1-ene.