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Ortho substituents on the aryl ring do not favor the Wagner-Meerwein rearrangement, as evidenced by adverse steric and electronic effects such as weaker resonance stabilization of the carbocation and steric encumbrance to nucleophilic attack. When the ortho substituent itself is nucleophilic, the barrier to Wagner-Meerwein rearrangement is overcome. This may be due to internal trapping of the carbocation to the exo side to yield a reactive intermediate that is predisposed to concerted bond migration. This was found in a study of the effect of ortho substituents on 1,2 migrations in 2-exo-arylfenchyl alcohols.

Brefeldin was synthesized with a highly selective conjugate addition of lithiated gamma-crotonolactone (but-2-en-4-olide) to cyclic enones to yield syn-adducts. Conjugate addition of lithiated butenolide served as an operational means of controlling installation of absolute configuration at oxygen-bearing functional groups exocyclic to the enone. The modified synthesis was found potentially useful in preparing brefeldin analogues.

Dilithiated allylic secondary amides were able to generate adducts during diastereoselective conjugate addition to cyclopentenone through C-gamma, demonstrating a non-allylic system attached charge-stabilizing group that generates the same high diastereo- and regiochemistry when used by a heteroatom. This ability may be useful in controlling reactions to design chiral amides for enantioselective reactions.