Alkylation and Arylation at Boron in NHC-Stabilized Phosphaborenes

Phosphaborenes, featuring a phosphorus-boron multiple bond, remain a relatively untapped area in chemical research due to the limited synthetic methods. Introducing leaving groups as substituents to the phosphorus or boron can pave the way for enhanced functionalization and modification. In this study, we present the synthesis of phosphaborenes featuring an N-heterocyclic boryl group on phosphorus and halogen substituent on boron, with stabilization provided by an N-heterocyclic carbene. Straightforward alkylation/arylation of these phosphaborenes is achieved by substituting the halogen with benzyl and aryl groups at the boron terminus. Our approach offers an efficient route to produce a diverse array of phosphaborene structures. The synthesis of phosphaborenes stabilized by N-heterocyclic carbene (NHC) and featuring halogen substituents on boron has been documented. These compounds demonstrate the capability for direct alkylation/arylation, allowing for structural variations at the boron site.+image