Mistake on TBR CBT 5?

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crazyasian

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I feel like this is a mistake in the test. On TBR CBT 5 It says the product of the aldol rxn is: Then says product 2 because Product 2 has all singlets because all the H's are isolated. but the Hydrogens on the phenyl group are neighboring each other and thus would be doublets (cuz n+1). Also it says that there are only 4 peaks which clearly should be more because not all the hydrogens on phenyl are equivalent. Can somebody take a look at the picture and tell me if I'm wrong. Thanks.

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I feel like this is a mistake in the test. On TBR CBT 5 It says the product of the aldol rxn is: Then says product 2 because Product 2 has all singlets because all the H's are isolated. but the Hydrogens on the phenyl group are neighboring each other and thus would be doublets (cuz n+1). Also it says that there are only 4 peaks which clearly should be more because not all the hydrogens on phenyl are equivalent. Can somebody take a look at the picture and tell me if I'm wrong. Thanks.

It ends up that there's a quirky issue with monosubstituted benzenes, where all 5 Hs blend together into one indistinguishable peak. So they treat them as all equivalent. With resonance and a 500Hz machine, you might be able to distinguish them, but at the level of the MCAT, they are all equivalent on monosubstituted benzenes.
 
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