Precise Synthesis of Chiral Phosphorus Compounds: From Robust Pincer Complexes to Chiral Brønsted Acid/Amide-Directed C–H Activation

Conspectus Chiral phosphines represent a cornerstone of molecular sciences, serving as the “privileged engines” that drive modern asymmetric catalysis. Despite their utility, the catalytic construction of chiral phosphorus compounds remains a formidable challenge, primarily because trivalent phosphorus nucleophiles tend to poison metal centers─a phenomenon we term the “Coordination Paradox”. Our laboratory has systematically addressed this bottleneck by pioneering two distinct catalytic manifolds governed by fundamentally different chemical principles. The first strategy centers on a “Logic of Robustness” designed to thwart the deactivation pathways triggered by phosphorus nucleophiles. By engineering rigid, tridentate PCP and PCP′ pincer complexes, we created a coordinatively protected environment for transition metals. This robust platform facilitated the first highly enantioselective 1,4- and 1,6-additions to diverse Michael acceptors, ultimately enabling the challenging asymmetric alkylation of primary phosphines. The second strategy pursues a logic of high atom-efficiency through direct synthesis. We introduced chiral phosphoric acids (CPAs) and carboxylic amides as stereocontrol elements in Pd- and Ir-catalyzed C–H bond activation. This approach does not merely supplement existing methods; it offers a direct route to structurally complex motifs─such as benzophosphole oxides and axially chiral biaryl phosphine. By participating in the concerted metalation-deprotonation (CMD) manifold, the CPA/amide directs the cleavage of enantiotopic C–H bonds with high fidelity. Furthermore, the development of novel nucleophiles, such as secondary phosphine sulfides and 2-pyridyl phosphine oxides, has resolved long-standing issues regarding regioselectivity and catalyst deactivation in allylic substitution and cross-coupling. Collectively, these advancements shift the field from labor-intensive stoichiometric methods toward an era of modular, atom-economical catalytic synthesis, providing a versatile toolkit for the chiral phosphorus community.