Erbium(III) chloride explained

Erbium(III) chloride is a violet solid with the formula . It is used in the preparation of erbium metal.

Preparation

Anhydrous erbium(III) chloride can be produced by the ammonium chloride route.^{[1] [2] [3]} In the first step, erbium(III) oxide is heated with ammonium chloride to produce the ammonium salt of the pentachloride:

In the second step, the ammonium chloride salt is converted to the trichloride by heating in a vacuum at 350-400 °C:

Structural data

Erbium(III) chloride forms crystals of the type, with monoclinic crystals and the point group C2/m.^[4]

Erbium(III) chloride hexahydrate also forms monoclinic crystals with the point group of P2/n (P2/c) - C⁴_2h. In this compound, erbium is octa-coordinated to form ions with the isolated completing the structure.^[5]

Optical properties

Erbium(III) chloride solutions show a negative nonlinear absorption effect.^[6]

Catalytic properties

The use of erbium(III) chloride as a catalyst has been demonstrated in the acylation of alcohols and phenols^[7] and in an amine functionalisation of furfural.^[8] It is a catalyst for Friedel–Crafts-type reactions, and can be used in place of cerium(III) chloride for Luche reductions.

Notes and References

1. Book: Handbook of Preparative Inorganic Chemistry. 2nd. Brauer, G. . Academic Press. 1963. New York.
2. Book: Meyer , G. . The Ammonium Chloride Route to Anhydrous Rare Earth Chlorides-The Example of YCl₃. The Ammonium Chloride Route to Anhydrous Rare Earth Chlorides—The Example of Ycl ₃. Inorganic Syntheses. 25. 1989. 146–150. 10.1002/9780470132562.ch35. 978-0-470-13256-2.
3. Book: Edelmann, F. T. . Synthetic Methods of Organometallic and Inorganic Chemistry . VI . Poremba, P. . Herrmann, W. A. . 1997 . Georg Thieme Verlag . Stuttgart . 978-3-13-103021-4 .
4. Tempelton DH, Carter GF . The Crystal Structure of Yttrium Trichloride and Similar Compounds . J Phys Chem . 1954 . 940–943 . 10.1021/j150521a002 . 58 . 11 .
5. Graebner EJ, Conrad GH, Duliere SF . Crystallographic data for solvated rare earth chlorides. . 1966 . 1012–1013 . 21 . 6. 10.1107/S0365110X66004420 .
6. Maeda Y, Akidzuki Y, Yamada T . All-optical liquid device derived from negative nonlinear absorption effect in an erbium chloride solution . Applied Physics Letters . 1998 . 73 . 2411–2413 . 10.1063/1.122450 . 17 . 1998ApPhL..73.2411M .
7. Dalpozzo Renato, De Nino Antonio, Maiuolo Loredana, Oliverio Manuela, Procopio Antonio, Russo Beatrice, Tocci Amedeo (2007) Erbium(iii) Chloride: a Very Active Acylation Catalyst. Australian Journal of Chemistry 60, 75-79.
8. Synthesis of trans-4,5-Bis-dibenzylaminocyclopent-2-enone from Furfural Catalyzed by ErCl3·6H2O Mónica S. Estevão, Ricardo J. V. Martins, and Carlos A. M. Afonso Journal of Chemical Education 2017 94 (10), 1587-1589