Alcohols are very useful starting materials for the production of many different compounds. The following conversions, starting with 1-butanol, can be carried out in two or more steps. Show the steps (reactants/catalysts) you would follow to carry out the conversions, drawing the formula for the organic product in each step. For each step, a major product must be produced. (See Exercise \(68 . )\) (Hint: In the presence of \(\mathrm{H}^{+},\) an alcohol is converted into an alkene and water. This is the exact reverse of the reaction of adding water to an alkene to form an alcohol.) $$ \begin{array}{l}{\text { a. } 1 \text { -butanol } \longrightarrow \text { butane }} \\ {\text { b. } 1 \text { -butanol } \longrightarrow 2 \text { -butanone }}\end{array} $$

For this conversion, we need to perform two reactions: dehydration and hydrogenation. 1. Dehydration of 1-butanol: In the presence of a strong acid catalyst like sulfuric acid (\(H_{2}SO_{4}\)) and heat, 1-butanol will lose a water molecule and form an alkene, 1-butene. $$ \text{1-butanol} \xrightarrow{H_{2}SO_{4}, \Delta} \text{1-butene} + \text{H}_{2}\text{O} $$ 2. Hydrogenation of 1-butene: Next, we will hydrogenate 1-butene to form butane. This is done using a catalyst, such as nickel (Ni), and hydrogen gas at an elevated temperature and pressure: $$ \text{1-butene} \xrightarrow{H_{2}, \text{Ni}} \text{butane} $$ Thus, the conversion of 1-butanol to butane follows these two steps.

For this conversion, we need to perform two reactions: oxidation and reduction. 1. Oxidation of 1-butanol: In the presence of an oxidizing agent, such as potassium dichromate (\(K_{2}Cr_{2}O_{7}\)), and an acid catalyst like sulfuric acid (\(H_{2}SO_{4}\)), 1-butanol is oxidized to form butanoic acid. $$ \text{1-butanol} \xrightarrow{K_{2}Cr_{2}O_{7}, H_{2}SO_{4}} \text{butanoic acid} $$ 2. Reduction of butanoic acid: Next, we can reduce butanoic acid to form 2-butanone (a ketone). This is done using a reducing agent like lithium aluminum hydride (\(LiAlH_{4}\)) followed by a hydrolysis step by adding water. $$ \text{butanoic acid} \xrightarrow{LiAlH_{4}} \text{Intermediate product} \xrightarrow{\text{H}_{2}\text{O}} \text{2-butanone} $$ Thus, the conversion of 1-butanol to 2-butanone follows these two steps.