Phosphorylation of allylic hydroxy groups via phosphite intermediates

Phosphitylation of an allylic hydroxy group with salicylchlorophosphite gives an allyl 1‐H‐phosphonate mono‐ester, which can be readily oxidized to the corresponding phosphate mono‐ester. Application of this phosphite‐triester approach was further demonstrated in the preparation of 1‐H‐phosphonate and phosphate mono‐esters of N‐protected trans‐zeatin.