The reaction described in the question involves a Lewis acid that reacts with LiAlH_4 to give a highly toxic gas. The gas in question is diborane (\( \text{B}_2\text{H}_6 \)), which is a highly toxic and volatile compound. When diborane reacts with ammonia (\( \text{NH}_3 \)), it forms a compound commonly known as inorganic benzene. This compound is known as borazine, \( \text{B}_3\text{N}_3\text{H}_6 \), which has a structure similar to benzene, but with alternating boron and nitrogen atoms. Thus, the gas that reacts with NH_3 to form inorganic benzene is \( \text{B}_2\text{H}_6 \).
The correct option is(C): \(B_2H_6\)
Ethanal to But-2-enal