Coinage Metal-Catalyzed Asymmetric Reactions of ortho-Alkynylaryl and Heteroaryl Aldehydes and Ketones

Abstract

Coinage metals have become the metal of choice due to their excellent catalytic activity in organic transformation processes. Combining various chiral ligands and coinage metals became a productive area of research and access to heterocyclic derivatives according to an efficient and sustainable manner. This review was devoted to the various recently developed coinage metal-catalyzed domino processes of ortho-alkynylaryl and heteroaryl aldehydes and ketones leading to functionalized heterocycles. Various gold chiral complexes were presented, and methods of preparations of chromenes along with indoles were covered. Ag-chiral complexes are also prone to interesting activities such as cyclization followed by reduction and functionalization with enolizable ketones or (diazomethyl)phosphonate. Asymmetric Cu-catalyzed domino cyclization and asymmetric transfer hydrogenation reactions efficiently led to functionalized chromenes. Some remarkable examples involving copper associated with ruthenium in the context of a cyclization and asymmetric hydrogenation process were also presented.

Enantioseparation of P-Stereogenic 1-Adamantyl Arylthiophosphonates and Their Stereospecific Transformation to 1-Adamantyl Aryl-H-phosphinates

“…Another characteristic of phopshothionates is that they contain a stable acidic P -stereogenic center, and in this regard these compounds can be considered as chiral Brønsted acids. P -contatining Brønsted acids found wide-spread application as organocatalysts, and BINOL-based C 2 -symmetric derivatives are benchmark catalysts [ 36 , 37 ]. A few studies suggested that C 1 -symmetric phopshothionates can also be used as organocatalysts, but in those instances, the catalyst scaffold contained other functional groups besides the P(S)OH moiety, and it was postulated that this combined activation is responsible for the asymmetric induction [ 38 , 39 , 40 , 41 ].…”