Where is the alcohol peak on 5-iodovanillin?

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The discussion centers on the identification of 5-iodovanillin, with the user confirming a melting point of 182.7-183.5 C, which aligns closely with the literature value of 183-185 C. However, the NMR spectrum does not display the expected alcohol peak, which is also minimally represented in the SDBS spectrum. A response from another forum suggests that the absence of the alcohol peak may be due to the rapid exchange of the phenolic proton, particularly since acetone was used in the experiment, and ketones have a lower pKa than phenols. The user concludes that this explanation resolves their concerns regarding the NMR results.
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So I'm pretty sure I got 5-iodovanillin. The melting point in the literature is 183-185 C and I got 182.7-183.5 C. But my NMR spectrum isn't showing the alcohol peak. It barely shows up on the SDBS spectrum also (http://sdbs.db.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi). Does anybody know why this is?
 

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Well I posted on another forum and they said that it is probably to to rapid exchange of the phenolic proton on there. Makes sense because I used acetone and ketones have a lower pka value than phenols. So yes it is solved. Thanks tho
 

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