Modular Assembly of Unsymmetric 3,4-Dihydro-BINAP Derivatives via Electrophilic Phosphinative Cyclization of Alkynes and Sequential C-P Cross-Coupling.

A modular assembly strategy has been developed for the efficient construction of BINAP-type derivatives featuring a novel 3,4-dihydrobinaphthyl backbone. The unsymmetric framework integrates four tunable modules. The presynthesized alkyne substrate bearing a naphthyl module undergoes a Tf2O-promoted phosphination/cyclization cascade process with diarylphosphine oxide to efficiently assemble the 3,4-dihydronaphthyl module along with the adjacent phosphine module. By employing a dinitrogen ligand, the subsequent nickel-catalyzed C-P cross-coupling reaction transfers the naphthyl-tethered triflate group into the second phosphine module with enhanced efficiency. The phosphoryl and thiophosphoryl groups were also introduced to modify the two distinct phosphine groups. In preliminary catalytic applications, 3,4-dihydro-BINAP outperforms the unmodified BINAP in two cases, highlighting the practical value of the ligand.