The compound that will not form a yellow precipitate on heating with an alkaline solution of iodine is:

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The reaction described is the **Iodoform test**. A positive test (formation of a yellow precipitate of $CHI_3$) is given by compounds containing either a methyl ketone group ($CH_3-C=O$) or a methyl carbinol group ($CH_3-CH(OH)-$) attached to at least one hydrogen atom or alkyl/aryl group.

1.  **Ethanol ($CH_3CH_2OH$):** Contains the $CH_3-CH(OH)-$ group. (Positive test).
2.  **Propan-2-ol ($CH_3CH(OH)CH_3$):** Contains the $CH_3-CH(OH)-$ group. (Positive test).
3.  **Butan-2-ol ($CH_3CH_2CH(OH)CH_3$):** Contains the $CH_3-CH(OH)-$ group. (Positive test).
4.  **Methanol ($CH_3OH$):** Does not contain the requisite $CH_3-CH(OH)-$ group. Therefore, it does **not** give a yellow precipitate with alkaline iodine.

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