Samarium(II) chloride explained

Samarium(II) chloride (SmCl₂) is a chemical compound, used as a radical generating agent in the ketone-mediated intraannulation reaction.

Preparation

Reduction of samarium(III) chloride with samarium metal in a vacuum at a temperature of 800 °C to 900 °C, or with hydrogen gas at 350 °C yields samarium(II) chloride:

2 SmCl₃ + Sm → 3 SmCl₂

2 SmCl₃ + H₂ → 2 SmCl₂ + 2 HCl

Samarium(II) chloride can also be prepared by reducing samarium(III) chloride with lithium metal/naphthalene in THF:^[1]

SmCl₃ + Li → SmCl₂ + LiCl

A similar reaction has been observed with sodium.

Structure

Samarium(II) chloride adopts the PbCl₂ (cotunnite) structure.

Notes and References

1. Rossmainth. Kurt. 1979-01-01. Herstellung der klassischen Seltenerd(II)-chloride in Lösung. Preparation of the classical rare earth(II) chlorides in solution. Anorganische, Struktur- und Physikalische Chemie. 110. 4. 109–114. 10.1007/BF00903752. 91731356 .