|Title||Proton-Coupled Electron Transfer in the Reduction of Arenes by SmI2–Water Complexes|
|Publication Type||Journal Article|
|Year of Publication||2015|
|Authors||Chciuk TV, Flowers, II RA|
|Journal||Journal of the American Chemical Society|
The presence of water has a significant impact on the reduction of substrates by SmI2. The reactivity of the Sm(II)-water reducing system and the relationship between sequential or concerted electron-transfer, proton-transfer is not well understood. In this work, we demonstrate that the reduction of an arene by SmI2-water proceeds through an initial proton-coupled electron transfer. The use of thermochemical data available in the literature shows that upon coordination of water to Sm(II) in THF, significant weakening of the O–H bond occurs. The derived value of nearly 73 kcal/mol for the decrease in the bond dissociation energy of the O–H bond in the Sm(II)–water complex is the largest reported to date for low-valent reductants containing bound water.