Question 14.3: What products would you expect from the following dehydratio...

What products would you expect from the following dehydration reaction? Which product will be major and which will be minor?

\begin{matrix}\,\,\,\,\,\,\,\,\,\,\, OH \\ CH_3\underset{|}{C} H\overset{|}{C} HCH_3 \\ CH_3\,\,\,\,\,\,\, \end{matrix} \stackrel{ H _2 SO _4}{\longrightarrow}?

ANALYSiS Find the hydrogens on carbons next to the OH-bearing carbon, and rewrite the structure to emphasize these hydrogens:

\begin{matrix}\,\,\,\,\,\,\,\,\,\,\, OH \\ CH_3\underset{|}{C} H\overset{|}{C} HCH_3 \\ CH_3\,\,\,\,\,\,\, \end{matrix}=\begin{matrix}\,\,\,\,\,\,\,\,\,H OH\,\,H\,\,\,\,\, \\ CH_3\underset{|}{\overset{|}{C}} \overset{|}{C} H\overset{|}{C}H_2 \\ CH_3\,\,\,\,\,\,\, \end{matrix}

Then, remove the possible combinations of —H and —OH, drawing a double bond each —H and —OH could be removed:

Finally, determine which alkene has the larger number of alkyl substituents on its double-bond carbons and is therefore the major product.