P‑Stereogenic Bicyclo[4.3.1]phosphite Boranes: Synthesis and Utility of Tunable P‑Tether Systems for the Desymmetrization of C2‑Symmetric 1,3-anti-Diols

The development of P-stereogenic bicyclo[4.3.1]­phosphite borane tether systems for the desymmetrization of C2-symmetric dienediols is reported. This report highlights preliminary studies including tether installation and removal as well as chemoselective functionalization of the exocyclic olefin via diimide reduction or cross-metathesis. Most notably, a divergent oxidation strategy allows for the transformation of the bicyclic phosphite borane complexes to the corresponding phosphate or thiophosphate systems, highlighting the electronic attenuation of this P-tether system.