The question is all about the sequence of a possible Birch- and Bouvault-Blanc-Reduction in this exemplary substrate. With which reduction the mechanism begin?

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My first attempt was to classify the aromatic system as a nucleophilic center, whereas the ester group as an electrophilic center. But as which should the solvated, "free" electron be classified? Maybe, because of its charge, simple as a nucleophilic reagent, which therefore first attacks the nucleophilic aromatic ring? Is this simple explanation right? Because in the Bouvault-Blanc reduction the attack also takes places on the nucleophile, partial negatively charged O-Atom.

This question was inspired by the II,5th Supplementary problem of the book "The Art of Problem solving in Organic Chemistry" (Alonso-Amelot, Second edition). There, the Birch reduction takes place first, but the author delivers (for me) no neat explanation.

  • $\begingroup$ What makes you think everything's electro/nucleophilic? SET reactions are neither. $\endgroup$ – Mithoron Jan 3 '19 at 21:56
  • $\begingroup$ @Mithoron Since I use the Clayden as my primary educational resource, I was until know convinced that it is also common to classify radicals as electrophile and nucleophile. See p. 995 "Organic Chemistry" (Clayden, Warren, Greeves), Second Edition But yeah, it does not make real sense for plain metal radicals. $\endgroup$ – Nilsfrank99 Jan 3 '19 at 22:10
  • $\begingroup$ Molecules can act as electro/nucleophiles, but electrons aren't classified as such and if electron is transferred not an atom it's not a "philic" reaction en.wikipedia.org/wiki/Outer_sphere_electron_transfer $\endgroup$ – Mithoron Jan 3 '19 at 22:33
  • $\begingroup$ @Mithoron Ok, thanks! Then the question remains: which reduction takes place first: Bouvault-Blanc or Birch? $\endgroup$ – Nilsfrank99 Jan 4 '19 at 8:07
  • $\begingroup$ Organic chemistry is an experimental science, at least historically. Do the reduction with a limited amount of sodium. Then analyze the product distribution. $\endgroup$ – user55119 Jan 5 '19 at 1:17

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