Metal triflimidate

A metal triflimidate^[1] M(NTf₂)_n in organic chemistry is a metal salt or complex of triflimidic acid and used as a catalyst.^[2]

Metal triflimidates are prepared by reaction of metal oxides, carbonates, hydroxides, or halides with triflimidic acid in water as the hydrate M(NTf₂)_n·xH₂O with x ranging from zero to nine. Another method is by metathesis reaction between a metal triflimidate and another metal complex by metal exchange. Commercially available salts are based on lithium and silver.

The catalytic activity of metal triflimidates has been demonstrated in cycloadditions, in various rearrangement reactions, in Friedel–Crafts acylation and Friedel–Crafts alkylation.

Lithium triflimidate is used as an electrolyte in batteries as a replacement of lithium perchlorate.

Gold phosphine or NHC triflimidates (LAuNTf₂, L = R₃P or NHC) are isolable though somewhat labile complexes of gold that serve as sources of catalytically-active LAu⁺ ions.^[3]

References

1. In the literature, such a salt is also called a metal triflimide or metal bistriflimide.
2. Antoniotti, S.; Dalla, V.; Duñach, E. (2010). "Metal Triflimidates: Better than Metal Triflates as Catalysts in Organic Synthesis—The Effect of a Highly Delocalized Counteranion". Angewandte Chemie International Edition. 49 (43): 7860–7888. doi:10.1002/anie.200906407. PMID 20715025.
3. Mézailles, Nicolas; Ricard, Louis; Gagosz, Fabien (2005-09-01). "Phosphine Gold(I) Bis-(trifluoromethanesulfonyl)imidate Complexes as New Highly Efficient and Air-Stable Catalysts for the Cycloisomerization of Enynes". Organic Letters. 7 (19): 4133–4136. doi:10.1021/ol0515917. ISSN 1523-7060. PMID 16146370.