(\(2-\) hydroxyprepane)gives yellow precipitate with iodine and alkali (iodoform test). But

\(C H_{3}-C O O-C H_{3}\) (methyl acetate), \(C H_{3}-C O-N H_{2}\)

(accetamide), do not perform this test because \(\alpha - H\) is not active due to \(+\mathrm{M}\) effect of nearby group.

\(\begin{matrix}
   C{{H}_{3}}-CH-C{{H}_{3}}  \\
   |\,\,\,\,\,  \\
   OH  \\
\end{matrix}\) \(+\,4{{I}_{2}}\,+\,6NaOH\to \,\underset{\begin{smallmatrix} 
 Iodoform \\ 
 (yellow\,\,ppt) 
\end{smallmatrix}}{\mathop{CH{{I}_{3}}}}\,\downarrow \) \(+\,C{{H}_{3}}COONa\,+\,5NaI\,+\,5{{H}_{2}}O\)