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JEE Main levelOne or more correct optionsDifficulty 2 of 3ap069

Which of the following give a positive iodoform test with $I X_{2}$ / $NaOH$ ?

Aethanol
Bpropan-2-ol
C1-phenylpropan-2-ol, $C X_{6} H X_{5} CH X_{2} CH (OH) CH X_{3}$
Dbutan-1-ol

Answer: A, B, C

The test is positive for ethanol and for compounds containing

CH X_{3} CH (OH) X^{-}

attached to H or carbon. Ethanol, propan-2-ol and 1-phenylpropan-2-ol all have this group and are oxidised to

CH X_{3} CHO

or a methyl ketone and then cleaved to

CHI X_{3}

. Butan-1-ol has no

CH X_{3} CH (OH) X^{-}

unit.

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