I am having an issue with this problem. I can think of 3 forms for this problem. Included in the attachment is the original form (not one of the 7) and the question. I am most confused about the E/Z isomers for this. I assume that some form of stereochem is used here, but I don't understand what.
There are a total of 7 "enol forms" when one considers alkene E/Z isomers plus the dienol tautomers (one of which contains the allene functional group). Draw all 7 enol forms of pentane-2,4-dione.
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Provides drawings for remaining enol forms.