Title: Niobium Pentachloride
CAS Registry Number: 10026-12-7
CAS Name: Niobium chloride (NbCl5)
Additional Names: columbium pentachloride; niobium(V) chloride
Molecular Formula: Cl5Nb
Molecular Weight: 270.17
Percent Composition: Cl 65.61%, Nb 34.39%
Line Formula: NbCl5
Literature References: Exists as dimeric units in the solid state. Prepn: Epperson et al., Inorg. Synth. 7, 163 (1963); cf. Rolsten, J. Am. Chem. Soc. 80, 2952 (1958). Toxicity studies: T. J. Haley et al., Toxicol. Appl. Pharmacol. 4, 385 (1962); N. A. Zhilova, A. A. Kasparov, Hyg. Sanit. 31, 328 (1966). Review of niobium halides: Fairbrother in Halogen Chemistry Vol. 3, V. Gutmann, Ed. (Academic Press, New York, 1967) pp 123-178. Review of applications in organic synthesis: C. K. Z. Andrade, Curr. Org. Synth. 1, 333-353 (2004).
Properties: Yellow, very deliquesc, monoclinic crystals; dec in moist air with evolution of HCl. d 2.75. mp 204.7-209.5°; bp ~250°, but begins to sublime at 125°. Sol in HCl, carbon tetrachloride. LD50 in mice (mg/kg): 61 i.p., 940 orally (Haley). LD50 in mice, rats (mg/kg): 829, 1400 orally (Zhilova, Kasparov).
Melting point: mp 204.7-209.5°
Boiling point: bp ~250°
Density: d 2.75
Toxicity data: LD50 in mice (mg/kg): 61 i.p., 940 orally (Haley); LD50 in mice, rats (mg/kg): 829, 1400 orally (Zhilova, Kasparov)
Use: Lewis acid catalyst in organic synthesis. |