title: Surprisingly mild "enolate-counterion-free"pd(0)-catalyzed intramolecular allylic alkylations.
abstract: [reaction: see text] Palladium-catalyzed intramolecular allylic alkylations of unsaturated EWG-activated amides can take place under phase-transfer conditions or in the presence of a crown ether. These new reaction conditions are milder and higher yielding than those previously reported. A rationalization for such an unexpected result is put forth and validated by DFT-B3LYP calculations. The results suggest cyclization via a counterion-free (E)-enolate TS.
authors.affiliation: Université Pierre et Marie Curie, UMR 7611 CNRS, 4 Place Jussieu, Tour 44-45, Boîte 183, F-75252, Paris, Cedex 05, France.
authors.forename: David
authors.initials: D
authors.lastname: Madec
authors.forename: Guillaume
authors.initials: G
authors.lastname: Prestat
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Martini
authors.forename: Peter
authors.initials: P
authors.lastname: Fristrup
authors.forename: Giovanni
authors.initials: G
authors.lastname: Poli
authors.forename: Per-Ola
authors.initials: PO
authors.lastname: Norrby