Copper(II) tetrafluoroborate
![]() | |
| Names | |
|---|---|
| IUPAC name
Copper(II) tetrafluoroborate | |
| Other names
Cupric tetrafluoroborate | |
| Identifiers | |
3D model (JSmol) |
|
| ChemSpider | |
| ECHA InfoCard | 100.049.037 |
PubChem CID |
|
CompTox Dashboard (EPA) |
|
| |
| |
| Properties | |
| Cu(BF4)2 | |
| Molar mass | 237.155 g/mol |
| Appearance | blue crystal |
| soluble in water | |
| Hazards | |
| GHS labelling:[2] | |
![]() ![]() | |
| Danger | |
| H302, H312, H314, H332 | |
| P260, P264, P270, P271, P280, P301+P317, P301+P330+P331, P302+P352, P302+P361+P354, P304+P340, P305+P354+P338, P316, P317, P321, P330, P362+P364, P363, P405, P501 | |
| NIOSH (US health exposure limits): | |
PEL (Permissible) |
TWA 1 mg/m3 (as Cu)[3] |
REL (Recommended) |
TWA 1 mg/m3 (as Cu)[3] |
IDLH (Immediate danger) |
TWA 100 mg/m3 (as Cu)[3] |
| Related compounds | |
Other anions |
Copper(II) chloride Copper(II) oxide Copper(II) triflate |
Other cations |
Sodium tetrafluoroborate Lithium tetrafluoroborate Silver tetrafluoroborate |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Infobox references | |
Copper(II) tetrafluoroborate or cupric tetrafluoroborate is any inorganic compound with the formula Cu(H2O)x(BF4)2. As usually encountered, it is assumed to be the hexahydrate (x = 6),[4] but this salt can be partially dehydrated to the tetrahydrate.[5] Regardless, these compounds are aquo complexes of copper in its +2 oxidation state, with two weakly coordinating tetrafluoroborate anions.
Applications
The compound is used in organic synthesis, e.g. as a Lewis acid for Diels Alder reactions, for cyclopropanation of alkenes with diazo reagents, and as a Lewis acid in Meinwald rearrangement reactions on epoxides.[6] In the former two applications, the copper(II) is reduced to a copper(I) catalyst.[5]
The compound is also used for copper electroplating in fluoroborate-based plating baths.[7]
References
- ↑ Lide, David R. (1998), Handbook of Chemistry and Physics (87 ed.), Boca Raton, Florida: CRC Press, pp. 4–56, ISBN 0-8493-0594-2
- ↑ PubChem. "Copper(II) fluoborate". pubchem.ncbi.nlm.nih.gov. Retrieved 2026-02-23.
- 1 2 3 NIOSH Pocket Guide to Chemical Hazards. "#0150". National Institute for Occupational Safety and Health (NIOSH).
- ↑ Vakulka, A., Goreshnik, E. Copper(II) Tetrafluoroborate Hexahydrate: Preparation, Structure and Raman Spectrum. J Chem Crystallogr 54, 157–162 (2024). https://doi.org/10.1007/s10870-024-01008-3
- 1 2 Ilhyong Ryu, Noboru Sonoda, "Copper(II) Tetrafluoroborate" Encyclopedia of Reagents for Organic Synthesis 2001, John Wiley & Sons. doi:10.1002/047084289X.rc249
- ↑ Robinson, Mathew W.C.; Pillinger, Kathryn S.; Graham, Andrew E. (August 2006). "Highly efficient Meinwald rearrangement reactions of epoxides catalyzed by copper tetrafluoroborate". Tetrahedron Letters. 47 (33): 5919–5921. doi:10.1016/j.tetlet.2006.06.055.
- ↑ Barauskas, Romualdas "Ron" (January 1, 2000). "Copper plating". Metal Finishing. 98 (1): 234–247. doi:10.1016/S0026-0576(00)80330-X. ISSN 0026-0576. Retrieved July 21, 2022.


