Equivalent hydrogens on NMR

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There was a question in TBR organic chem that asked how the H NMR would change for the molecule following this grignard step?

The answer was that it would gain three signals.

Wouldn't it gain 5 new signals though?

Compound K has two sets of equivalent hydrogens, and then a single hydrogen attached to the bottom carbon.

In compound R, the molecule becomes asymmetric. In addition to the new hydrogens on the alcohol and the ethyl group, aren't the previously equivalent hydrogens no longer in the same electronic environments?


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Dec 5, 2017
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I think you go from 3 signals to 6 signals. I don't think there are diastereomeric hydrogens on the ring before or after the reaction because of ring flipping.
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