Divalent samarium reagents

The single electron transfer reagent samarium(II) diiodide (SmI₂) has rapidly become a widely used reagent for selective reduction and reductive coupling reactions.

We have recently discovered that addition of H₂O and an aliphatic amine results in a very powerful reductant. The SmI₂/H₂O/amine mixture has been found to mediate quantitative and instantaneous reductions of a wide variety of functional groups. In addition, H₂O is used as a very cheap and non-explosive hydrogen source.

The long-term goal is to determine the scope and the limitations of the SmI₂/H₂O/amine reagent for various reduction reactions. Mechanistic methods can constitute a tool for further development of this class of chemistry. The use of other lanthanide(II) reagents (i.e. SmBr₂ and YbI₂) in combination with amine and water is currently being explored.