Palladium-Catalyzed Enantioselective Allylic Substitution

Abstract

Palladium-catalyzed allylic substitution is one of the main reactions for testing new chiral ligands. The most relevant examples from the work published in the period 2007 to mid-2010 are reviewed. The vast majority of the work published within this timeframe relies upon the application of chiral ligands for asymmetric induction. The recent advances in the development and applications of new chiral P-P, P-N, P-O, P-S, N-N, N-S, S-S, and NHC ligands are covered and are the main focus of this chapter. Other aspects of enantioselective palladium allylic alkylations are discussed in the subsequent sections, for example, heterogeneous catalysis, the use of chiral salt additives, and recent applications in kinetic resolution.

Synthesis and Simple Immobilization of Palladium(II) Acyclic Diaminocarbene Complexes on Polystyrene Support as Efficient Catalysts for Sonogashira and Suzuki–Miyaura Cross-Coupling

“…Among palladium-catalyzed reactions, great attention has been paid to C–C bond formation, which is regarded as a convenient methodology that simplifies the synthesis of complex organic molecules, natural product precursors, pharmaceuticals and advanced materials. − The importance, scope, and potential of cross-coupling chemistry for both academia and industry were marked by the Nobel Prize for Chemistry in 2010, which was awarded to Richard F. Heck, Ei-ichi Negishi, and Akira Suzuki “for palladium-catalyzed cross couplings in organic synthesis”. ,− …”

Construction of Vicinal Quaternary Carbon Centers via Cobalt-Catalyzed Asymmetric Reverse Prenylation

“…Transition-metal-catalyzed allylic substitution reactions provide efficient ways to construct new carbon–carbon and carbon–heteroatom bonds . Palladium plays the most important role in this key transformation . However, it usually produces linear products when unsymmetric allylic substrates are used for steric reasons.…”

Iridium-Catalyzed Diastereo-, Enantio-, and Regioselective Allylic Alkylation with Prochiral Enolates

“…1 Within this field, palladium-catalyzed allylic alkylation reactions have undoubtedly been the most studied. 2 Aside from limited cases, 3 palladium catalysts preferentially form the linear substitution product through alkylation at the less-substituted terminus of the allylic electrophile (Scheme 1). However, in contrast to palladium, most other transition metals (e.g., Mo, W, Fe, Ru, Co, Rh, Ni, Pt, and Ir) have been shown to favor the construction of the branched product, with iridium catalysts being some of the most efficient and selective.…”