Which of the following statement is wrong : - Vidyadip

MCQ

Which of the following statement is wrong :

A
All carbonyl compounds of the general structure $\begin{array}{*{20}{c}}
{C{H_3} - C - R} \\
{\,\,\,\,\,||} \\
{\,\,\,\,O}
\end{array}$ give a positive iodoform test
✓
All secondary alcohols give iodoform reaction
C
Alkanols of the structure $CH_3CH(OH) -R$ (where $R = H,$ alkyl or aryl) give iodoform reaction.
D
The only aldehyde giving iodoform reaction is acetaldehyde.

✓

Answer

Correct option: B.

All secondary alcohols give iodoform reaction

b
Any compound which gives chloroform test should contain the $CH _3 CO$ - group in its structure.

So, only aldehyde (RCHO) giving iodoform reaction is acetaldehyde $\left( CH _3 CHO \right)$

Alcohols of the structure $CH _3 CH ( OH ) R$ give iodoform reaction, as, on oxidation, it is converted into $CH _3 COR$.

But other $2^{\circ}$ alcohols will not give this test.

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