Niobium (V) chloride

Structural formula
General
Surname	Niobium (V) chloride
other names	Niobium pentachloride
Molecular formula	NbCl 5
Brief description	yellow solid with a pungent odor
External identifiers / databases
CAS number 10026-12-7 EC number 233-059-8 ECHA InfoCard 100.030.042 PubChem 24818 ChemSpider 23203 Wikidata Q417510
properties
Molar mass	270.17 g mol −1
Physical state	firmly
density	2.75 g cm −3
Melting point	208.3 ° C ( decomposition )
boiling point	248.2 ° C
solubility	violent decomposition in water
safety instructions
GHS labeling of hazardous substances danger H and P phrases H: 302-314 EUH: 014-071 P: 280-301 + 330 + 331-305 + 351 + 338-310-402 + 404
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Niobium (V) chloride is a salt-like chemical compound consisting of the elements niobium and chlorine .

Extraction and presentation

Niobium (V) chloride can be obtained by reacting niobium with chlorine.

${\displaystyle \mathrm {2\ Nb+5\ Cl_{2}\longrightarrow \ 2\ NbCl_{5}} }$

It is also possible to produce it by reacting niobium (V) oxide with thionyl chloride or carbon tetrachloride or hexachloropropene :

${\displaystyle \mathrm {Nb_{2}O_{5}+5\ SOCl_{2}\longrightarrow 2\ NbCl_{5}+5\ SO_{2}} }$

${\displaystyle \mathrm {Nb_{2}O_{5}+5\ CCl_{4}\longrightarrow 2\ NbCl_{5}+5\ COCl_{2}} }$

${\displaystyle {\ce {Nb2O5 + 5 CCl2=CClCCl3 -> 2 NbCl5 + 5 CCl2=CClCOCl}}}$

properties

Niobium (V) chloride

It is a yellow solid with a pungent odor (formation of hydrogen chloride by hydrolysis ) that decomposes violently in water.

Niobium (V) chloride forms a dimeric structure in which each niobium atom is six-fold coordinated by chloro ligands . Two chlorine atoms act as bridging ligands . There are two crystalline polymorphs of niobium (V) chloride; a distorted octahedral structure is formed in both , in which the pseudo-axial chloro ligands are arranged at an angle of approx. 84 ° to the pseudo-equatorial plane.

use

Niobium (V) chloride is used as a Lewis acid in organic chemistry . For example, it is used in the activation of alkenes in the carbonyl-ene reaction .

Individual evidence

1. ↑ ^{a b c d e f g} Entry on niobium (V) chloride in the GESTIS substance database of the IFA , accessed on July 23, 2016(JavaScript required) .
2. ↑ ^{a b} Georg Brauer (Ed.) U. a .: Handbook of Preparative Inorganic Chemistry. 3rd, revised edition. Volume III, Ferdinand Enke, Stuttgart 1981, ISBN 3-432-87823-0 , p. 1444.
3. ^ WW Porterfield and SY Tyree, Jr .: Anhydrous metal chlorides . In: S. Young Tyree, Jr. (Ed.): Inorganic Syntheses . tape 9 . McGraw-Hill Book Company, Inc., 1967, p. 133-136 (English).
4. ↑ W. Hoenle, H. G. v. Schnering: Crystal structure of niobium pentachloride . In: Zeitschrift für Kristallographie '' , 1990 , 191 , pp. 139–140 ( doi : 10.1524 / zkri.1990.191.1-2.139 )
5. ↑ FA Cotton, PA Kibala, M. Matusz, RBW Sandor in: Structure of the Second Polymorph of Niobium Pentachlorid 1997 , Acta Crystallographica C47 , pp. 2435-2437 ( doi : 10.1107 / S0108270191000239 ).
6. ↑ CKZ Andrade, OE Vercillo, JP Rodrigues, DP Silveira in J. Braz. Chem. Soc. 2004, 15, 6, 813-817.