Question

$ 2{{C}_{6}}{{H}_{5}}CHO\xrightarrow{NaOH}{{C}_{6}}{{H}_{5}}C{{H}_{2}}OH+{{C}_{6}}{{H}_{5}}COONa $ The same reaction can take place with which ofthe following aldehydes ?

• A. $ C{{H}_{3}}CHO $
• B. $ C{{H}_{3}}C{{H}_{2}}CHO $
• C. $ {{(C{{H}_{3}})}_{3}}CCHO $
• D. $ {{(C{{H}_{3}})}_{2}}CHCHO $

Answer 1

Answer: (C)

The given reaction is Cannizaro reaction. It is given by only those aldehydes in which $ \alpha -H $ atom is not present. Hence, $ {{\text{(C}{{\text{H}}_{\text{3}}}\text{)}}_{\text{3}}}\text{C}\text{.CHO} $ due to the absence of $ \alpha -H $ atom gives the Cannizaro reaction as $ 2{{(C{{H}_{3}})}_{3}}C.CHO\xrightarrow{\text{Conc}\text{.}\,\text{NaOH}}{{(C{{H}_{3}})}_{3}}C.C{{H}_{2}}OH $ $ +{{(C{{H}_{3}})}_{3}}C.COONa $ $ {{\text{(C}{{\text{H}}_{\text{3}}}\text{)}}_{\text{2}}}\text{CHCHO} $ also give Cannizaro reaction, however in if $ \alpha -H $ atom is present