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I can see how the option A and B are correct as it is just a standard dienone–phenol type reaction which involves a phenyl shift. However, the given answer is A, B, C and D.
I do not see how C and D are formed. Does the presence of light affect the reaction? If so, how?
The formation of structure 6 (your D) occurs as follows. Photolysis of dienone 1 affords excited state 2 that forms cyclopropane 3. In turn, 3 is capable of breaking a different cyclopropane bond to form 5-membered ring 4. Structure 5 is a resonance structure of 4. Structure 5 closes to the [3.1.0] product 6 (your D). I don't know how you formed A (12 here) but further photolysis of 6 can form 12 via a bridged phenyl migration as shown in structure 9. A similar migration in structure 2 leads to your B. Of course, structure C has only five carbons and was added to the choices as a trap. See reference 1 for an example of a dienone phenol rearrangement.
1) A. G. Schultz and S. A. Hardinger, J. Org. Chem., 1991, 56, 1105.
The above answer is totally Correct but for your information, if light was not there then there would have been a RETRO PINACOLE-PINNACOLON REARRANGEMENT.
