Photocatalyzed Synthesis of Unsymmetrical Alkylphosphorus(V) Compounds Using Imidazolium Phosphonites

Abstract

Abstract Here, we report a synthetic approach for a wide range of unsymmetrical alkylphosphorus(V) compounds, alkyl‐P(O)XY (X ≠ Y) using imidazolium phosphonites as bifunctional reagents. This protocol consists of two sequences, C(sp 3 )─P bond formation via an organic photoredox‐catalyzed decarboxylative alkylation of imidazolium phosphonites with aliphatic carboxylic acid derivatives and P─X (X═O, N, F, and S) bond formation via the S N P(V) reaction. In this process, the imidazolium group facilitates 1) radical addition to the phosphonite reagent by stabilizing the resulting phosphoranyl radical intermediate and 2) the S N P(V) reaction as a good leaving group. This protocol allows the introduction of primary , secondary and tertiary alkyl substituents and various heteroatom substituents onto P(V) scaffolds.