|Title||Proton-Coupled Electron Transfer in the Reduction of Carbonyls by Samarium Diiodie-Water Complexes|
|Publication Type||Journal Article|
|Year of Publication||2016|
|Authors||Chciuk T, Anderson WR, Flowers, II RA|
|Journal||Journal of the American Chemical Society|
Reduction of carbonyls by SmI2 is significantly impacted by the presence of water, but the fundamental step(s) of initial transfer of a formal hydrogen atom from the SmI2−water reagent system to produce an intermediate radical is not fully understood. In this work, we provide evidence consistent with the reduction of carbonyls by SmI2−water proceeding through protoncoupled electron transfer (PCET). Combined rate and computational studies show that a model aldehyde and ketone are likely reduced through an asynchronous PCET, whereas reduction of a representative lactone occurs through a concerted PCET. In the latter case, concerted PCET is likely a consequence of significantly endergonic initial electron transfer.