Such chiral phosphine–internal olefin hybrid type ligands as N-1-adamantyl-N-cinnamylaniline derivatives 1 with C(aryl)–N(amine) bond axial chirality were synthesized and utilized for the palladium-catalyzed asymmetric allylicalkylation of indoles to afford the desired products in high enantioselectivities (up to 98% ee).
We synthesized a series of phosphine–olefin-type chiral aminophosphines, and we confirmed that these each exists as two rotamers at the C(aryl)–N(amine) bond. We also investigated the ability of these aminophosphines to act as chiralligands for Pd-catalyzed asymmetricallylicsubstitutionreactions, such as the alkylation of allylic acetates with malonates or indoles, and we found they gave high
The palladium-catalyzed asymmetric allylicalkylation of indoles with 1,3-diphenyl-2-propenyl acetate using P/N-type ligands such as N-aryl indole, C–N bond axially chiral aminophosphine (aS)-L4, gave the desired products 1 in good yields and with moderate to high enantioselectivities (up to 90% ee).