Synthesis of Tetraarylphosphonium Salts from Triarylphosphines and Aryl Bromides Exploiting Light and Palladium

We herein report that an onium salt -forming reaction of triarylphosphines with aryl bromides is promoted by the sequential cooperation of light with palladium. The mild reaction conditions tolerate various functionalities such as amino and hydroxy groups, and thus, the present method offers a convenient and expedient access to variously substituted tetraarylphosphonium salts.

Automated summary

In this study, we demonstrate that the onium salt-forming reaction of triarylphosphines with aryl bromides can be efficiently promoted by the sequential cooperation of light with palladium. The reaction conditions are mild and tolerant of various functional groups such as amino and hydroxy groups, providing a convenient and expedient access to variously substituted tetraarylphosphonium salts.