Question:
The aldehydes which will not form Grignard product with one equivalent Grignard reagents are :
Correct Option: 1
Solution:
Grignard reagent will not react with aldehydes if it has a functional group which contains acidic hydrogen. Thus options (B) and(D) have - $\mathrm{COOH}$ and $-\mathrm{CH}_{2} \mathrm{OH}$ respectively which contain acidic $\mathrm{H}$-atom. Therefore, acid-base reaction occurs.