Tethered Silanoxyiodination of Alkenes

We present the first examples of tethered silanoxyiodination reactions of allylic alcohols. The products are useful silanediol organoiodide synthons and are formed with high regioselectivity and diastereocontrol. The reaction is scalable greater than 10-fold without loss of yield or selectivity. Furthermore, the products are starting materials for further transformations, including de-iodination, C–N bond installation, epoxide synthesis, and de-silylation. DFT calculations provide a basis for understanding the exquisite 6-endo selectivity of this silanoxyiodination reaction and show that the observed products are both kinetically and thermodynamically preferred.