Functionalization of λ⁵-Phosphinines via metalation strategies

Phosphinines, or phosphabenzenes, exhibit distinctive electronic properties yet remain underexplored due to the challenges associated with their selective functionalization. We present herein the straightforward functionalization of λ⁵-phosphinine derivatives using organometallic strategies. Halogen-zinc and -magnesium exchanges were successfully performed employing Et₂Zn·2Oamyl or i-PrMgCl·LiCl species under smooth reaction conditions. Such method allowed access to a wide range of sophisticated architectures, photophysical studies of which demonstrated interesting fluorescence properties. With the possibility of using such fluorescence in biomarking, λ⁵-phosphinines were grafted on a few glycosides, nucleosides and pharmaceutically relevant moieties.