Synthesis of P-Stereogenic Phosphinamides via Pd(II)-Catalyzed Enantioselective C-H Alkynylation

P-Stereogenic phosphinamides representimportantstructural elements in chiral organocatalysts and bioactive compounds.Herein, we report Pd(II)-catalyzed enantioselective C-H alkynylationusing cheap commercially available l-pyroglutamic acid asa chiral ligand. A range of structurally diverse P-stereogenic phosphinamides was prepared in good yields with highenantioselectivities via desymmetrization and kinetic resolution.A tailor-made congested directing group, N-ethyl-N-(3-methylpyridin-2-yl)amino, was crucial for the reactivity.

Automated summary

In this study, we describe the preparation of various structurally diverse P-stereogenic phosphinamides through Pd(II)-catalyzed enantioselective C-H alkynylation using cheap commercially available l-pyroglutamic acid as a chiral ligand. The reactions showed good yields and high enantioselectivities via desymmetrization and kinetic resolution. The presence of a tailor-made congested directing group, N-ethyl-N-(3-methylpyridin-2-yl)amino, was crucial for the reactivity.