Cu(CO)₂(N(SO₂CF₃)₂). The First Structurally Characterized Copper(I) Polycarbonyl

Abstract

nate Cu + ion bonded to the sulfonamide nitrogen atom and to two CO ligands with long Cu-C bonds (1.90 and 1.91 Å) and a C-Cu-C bond angle of 122°. The two ν(CO) IR bands for this compound are at 2158 (s) and 2184 (m) cm -1 .Copper(I) carbonyls have long been of interest to chemists. 1 They are formed in many catalytic transformations of CO 2 and in the purification of CO from steam-methane-reforming gases. 3 In addition, CO is used as a probe ligand for studying reduced coppercontaining proteins and enzymes. 4 Finally, the ν(CO) values of copper(I) carbonyls can be either higher or lower than 2143 cm -1 , the value for gaseous CO. This makes copper(I) carbonyls of pivotal importance in understanding and refining the distinction between classical and nonclassical metal carbonyls. 5 Virtually all copper(I) carbonyl complexes studied to date have a stoichiometry Cu:CO ) 1:1. 6 Nevertheless, there are some important exceptions. In a seminal paper in 1976, Souma and co-workers reported that Cu + ions dissolved in strong protic acids could absorb up to 4(1) (a) Leblanc, F.

Cu(I)/O2 Chemistry Using a β-Diketiminate Supporting Ligand Derived from N,N-Dimethylhydrazine: A [Cu3O2]3+ Complex with Novel Reactivity

“…Rationale (a) seems unlikely because while several [Cu(CO) 2 ] + species have been reported (cf. entry 2, Table 1), 16,27–31 they display ν(CO) values higher in energy than free CO (2143 cm −1 ) due to competition between the multiple CO ligands for dp electron density at the metal center. 27 In support of rationale (b), equilibria between Cu(I) species with bridging or terminal CO ligands (Figure 3) have been described for complexes supported by bidentate peralkylated diamines, which exhibit a pattern of ν(CO) values similar to that which we observe (entries 4–6, Table 1).…”

“…entry 2, Table 1), 16,27–31 they display ν(CO) values higher in energy than free CO (2143 cm −1 ) due to competition between the multiple CO ligands for dp electron density at the metal center. 27 In support of rationale (b), equilibria between Cu(I) species with bridging or terminal CO ligands (Figure 3) have been described for complexes supported by bidentate peralkylated diamines, which exhibit a pattern of ν(CO) values similar to that which we observe (entries 4–6, Table 1). 18 We deem it likely that a similar equilibrium occurs for our system, with the caveat that we have not performed more extensive characterization to support this hypothesis unambiguously.…”

Copper(I)‐Containing Ionic Liquids for High‐Rate Electrodeposition

“…The most similar compound found in the literature is Cu(CO) 2 Tf 2 N, which also contained a three-coordinate Cu centre, but with two C atoms and an N atom coordinating, but the melting point of this compound was not given. [14] The conductivity of liquid…”

“…The two twin components were integrated together and an absorption correction applied with TWINABS. [20] The proportion of the twin components refined to 0.4860 (14). The program OLEX2 was also used in refinement and making pictures.…”

Crystal structures of low-melting ionic transition-metal complexes with N-alkylimidazole ligands

“…By comparing the Co(II), Ni(II) and Cu(II) containing ionic liquids, an interesting dependence of the melting points on the composition of the metal complex has been observed. To date, there have been very few crystal structures of Co, Ni or Cu complexes containing the bis(trifluoromethylsulfonyl)imide anion, 10,13,17,[22][23][24][25][26][27] so the effect of this anion on the crystal packing in metal complexes is little understood. Due to the charge distribution and the weak intermolecular interactions, the bis(trifluoromethylsulfonyl)imide anion is a good candidate to make low-melting or even roomtemperature metal-containing ionic liquids.…”