Enantioselective total and formal syntheses of paroxetine (PAXIL) via phosphine-catalyzed enone α-arylation using arylbismuth(V) reagents: a regiochemical complement to Heck arylation

Exposure of dihydropyridinone 1 to the arylbismuth(V) reagent (p-F-Ph)3BiCl2 in the presence of substoichiometric quantities of tributylphosphine results in aryl transfer to the transiently generated (β-phosphonio)enolate, ultimately providing the α-arylated enone 2. This transformation, which represents a regiochemical complement to the Mizoroki-Heck arylation, is used strategically in concise formal and enantioselective total syntheses of the blockbuster antidepressant (−)-paroxetine (PAXIL).