This conversion was recently asked in the NSEC, an Indian (preliminary) chemistry olympiad for high schoolers and the official answer key stated LiAlH4 is the correct reagent to be used. However I have come across LAH reducing double bonds conjugated with benzene rings so I thought the double bond would be reduced if it was used. Therefore I assumed the birch reduction would be the appropriate method, but would that reduce the ring itself into some sort of diene? Or is that just for unsubstituted benzene? The other options were the clemmenson (which would kill the carbonyl) and H2/Pd-C (which should kill the double bond)
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1$\begingroup$ We had this come up recently and maybe someone smarter than me can find the discussion. The real world answer is that none of the four reagents offered will do this reliably. Modified borohydride is the way to go, either Luche reduction en.wikipedia.org/wiki/Luche_reduction or sodium monoacetoxyborohydride pubs.acs.org/doi/10.1021/jo00284a046 $\endgroup$– WaylanderCommented Dec 22, 2023 at 15:03
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1$\begingroup$ Found it chemistry.stackexchange.com/questions/177916/… $\endgroup$– WaylanderCommented Dec 22, 2023 at 15:28
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$\begingroup$ Lanthanide modified LiAlH4 will also give the allylic alcohol pubs.rsc.org/en/content/articlelanding/1986/p1/p19860001929 $\endgroup$– WaylanderCommented Dec 22, 2023 at 15:31
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$\begingroup$ Thank you so much! A lot of times in these types of questions its more of which of the following is least wrong, more than which does the job effectively haha. It is difficult to teach us so much material in such a short time, so yeah nuance is lost sometimes. $\endgroup$– Gaurav Sai MaddipatiCommented Dec 22, 2023 at 15:43
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