Iridium carbonyl compounds from the reaction of Ir4(CO)12 with sodium

Malatesta, L.; Caglio, G.; Angoletta, Maria Elena

doi:10.1039/c29700000532

Cited by 27 publications

(21 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Our BP86 frequency calculations confirm these assignments, with scale factors ranging from 0.987 to 1.008. Note again the large carbon isotopic dependence for the monocarbonyl anion absorption and agreement with the solution absorption 16 for Ir(CO) 4 -at 1898 cm -1 .…”

Section: Discussionsupporting

confidence: 61%

“…Earlier thermal Co, Rh, and Ir atom matrix isolation investigations identified neutral M(CO) 1 - 4 species in solid argon. , In addition, laser-ablation experiments with cobalt formed the M(CO) 1 - 4 - anions, and the stable Co(CO) 4 - anion gave the same infrared absorption as found in THF solution . We report here reactions of laser-ablated Co, Rh, and Ir with CO in excess neon, which produce better resolved neutral species and in addition the first infrared spectra of group 9 metal carbonyl cation and anion species, except for the stable tetracarbonyl anions in solution, , which are in agreement. Matrix infrared observation of the simple MCO +,0,- monocarbonyl series provides a scale by which a metal charge in larger complex ions and supported catalysts sites can be estimated.…”

Section: Introductionmentioning

confidence: 58%

“…The 1828.6 cm -1 band and 1826.7 cm -1 satellite give a doublet mixed isotopic absorption ( Figure 6, bars connect isotopic counterparts) for the vibration of a single carbonyl. Our BP86 calculations predict the RhCO -absorption at 1843.6 cm -1 with unique large 1.0268 and small 1.0186 isotopic 12 C/ 13 C and 16 A 1814.4 cm -1 site of the 1816.7 cm -1 band and an associated 1900.4 cm -1 feature increase on 8 K annealing, and the 1816.7 cm -1 band decreases 5% on λ > 290 nm photolysis while the remaining two bands slightly increase. The mixed 12 CO, 13 CO spectrum reveals triplet patterns and two equivalent carbonyls for these absorptions and suggests the Rh(CO) 2 -assignment.…”

Section: Discussionmentioning

confidence: 97%

See 2 more Smart Citations

Reactions of Laser-Ablated Co, Rh, and Ir with CO: Infrared Spectra and Density Functional Calculations of the Metal Carbonyl Molecules, Cations and Anions in Solid Neon

1999

View full text Add to dashboard Cite

Laser ablation produces metal atoms, cations, and electrons for reaction with CO during condensation in excess neon at 4 K. Infrared spectra are observed for the metal carbonyls, cations, and anions, which are identified from isotopic shifts ( 13 CO, C 18 O) and splittings using mixed isotopic precursors. Density functional calculations with pseudopotentials for Rh and Ir predict the observed carbonyl stretching frequencies within 1-2%. This characterization of the simple RhCO + , RhCO, and RhCO -(and Ir) species over a 350 cm -1 range provides a scale for comparison of larger catalytically active Rh and Ir carbonyl complexes in solution and on surfaces to estimate charge on the metal center. This work provides the first spectroscopic characterization of Rh and Ir carbonyl cations and anions except for the stable tetracarbonyl anions in solution.

show abstract

Section: Discussionsupporting

confidence: 61%

Section: Introductionmentioning

confidence: 58%

Section: Discussionmentioning

confidence: 97%

See 1 more Smart Citation

Reactions of Laser-Ablated Co, Rh, and Ir with CO: Infrared Spectra and Density Functional Calculations of the Metal Carbonyl Molecules, Cations and Anions in Solid Neon

1999

View full text Add to dashboard Cite

show abstract

“…[1] In this paper we report the NMR characterization of two carbonyliridium clusters, namely [Ir 6 (CO) 15 ] 2-and Ir 6 (CO) 16 . Both compounds have been previously synthesized in 1970 by Malatesta and co-workers, [3] but only in the middle of the 1980s did we manage to determine the cluster's structures. [Ir 6 (CO) 15 ] 2-shows 12 terminal and three edge-bridging CO ligands, [4] while Ir 6 (CO) 16 has been isolated in two different isomeric forms: a red and a black isomer, the latter being quite unstable.…”

Section: δ(Co-co) ͼ δ(Rh-co) ͼ δ(Ir-co)mentioning

confidence: 99%

An Unusual Carbonyl Chemical Shift in a Carbonylhexairidium Cluster: A Combined Solid‐State NMR and DFT Approach

et al. 2007

View full text Add to dashboard Cite

“…However, the paramagnetic d 9 -valence-electron-configured [M(CO) 4 ] complexes were only observed in inert-gas matrices at very low temperatures [8 ± 10]. On the other side, the colorless anionic d 10 -valence-electron-configured [M(CO) 4 ] À ions are quite stable and were prepared in form of various alkali metal and NH 4 salts ([Rh(CO) 4 ] À : [11], [Ir(CO 4 )] À : [12]). When fluorophosphines like PF 3 or PF 2 NMe 2 are used as electron-withdrawing ligands, a similar picture arises, i.e., the complex anions [M(PF 3 ) 4 ] À (M Rh, Ir) ([Rh(PF 3 ) 4 ] À : [13], [Rh(PF 3 ) 4 ] À and [Ir(PF 3 ) 4 ]: [14]) or [Rh(PF 2 NMe 2 ) 4 ] ([Rh(PF 2 NMe 2 ) 4 ]: [15]) are easily prepared and isolated, while the neutral [M(PF 3 ) 4 ] complexes could not be characterized, and the dimers [M 2 (PF 3 ) 8 ] were isolated instead.…”

mentioning

confidence: 99%

Protonation and Hydrogenation Experiments with Iridium(0) and Iridium(−1) tropp Complexes: Formation of Hydrides

Böhler¹,

Avarvari²,

Schönberg³

et al. 2001

HCA

View full text Add to dashboard Cite

Dedicated to the memory of Professor Luigi M. VenanziThe reactions of three different tetracoordinated Ir complexes, [Ir(tropp ph ) 2 ] n (n 1, 0, À 1), which differ in the formal oxidation state of the metal from 1 to À 1, with proton sources and dihydrogen were investigated (tropp 5-(diphenylphosphanyl)dibenzo[a,d]cycloheptene). It was found that the cationic 16-electron complex [Ir(tropp ph ) 2 ] (2) cannot be protonated but reacts with NaBH 4 to the very stable 18-electron Ir I hydride [IrH(tropp ph ) 2 ] (5), which is further protonated with medium strong acids to give the 18-electron Ir III dihydride [IrH 2 (tropp ph ) 2 ] (6; pK s in CH 2 Cl 2 /THF/H 2 O 1:1:2 ca. 2.2). Both, the neutral 17-electron Ir 0 complex [Ir(tropp ph ) 2 ] (3) and the anionic 18-electron complex [Ir(tropp ph ) 2 ] À (4) react rapidly with H 2 O to give the monohydride 5. In reactions of 3 with H 2 O, the terminal Ir I hydroxide [Ir(OH)(tropp ph ) 2 ] (8) is formed in equal amounts. All these complexes, apart from 5, which is inert, do react rapidly with dihydrogen. The complex 2 gives the dihydride 6 in an oxidative addition reaction, while 3, 4, and 8 give the monohydride 5. Interestingly, a salt-type hydride (i.e., LiH) is formed as further product in the unexpected reaction with [Li(thf) x ] -[Ir(tropp ph ) 2 ] À (4). Because 3 undergoes disproportionation into 2 and 4 according to 2 3>2 4 (K disp 2.71 0 À5 ), it is likely that actually the diamagnetic species and not the odd-electron complex 3 is involved in the reactions studied here, and possible mechanisms for these are discussed.Introduction. ± Rh and Ir complexes in their formal oxidation states of 0 and À 1 have a promising potential in bond-activation chemistry (for an early report on Reppetype hydroformylations with Rh 0 carbonyls, see [1]; for CÀH activation, see [2]; for electrochemical CO 2 reduction with [RhCl(dppe) 2 ], see [3]; for electrochemical CO 2 reduction with [MCl(CO)(PPh 3 ) 2 ] (M Rh,Ir), see [4]; for chemical reduction with [BrMg] [Rh(Ph 2 PÀ(Ch 2 ) n ÀPPh 2 ] À (n 2, 3), see [5]; for hydroformylation, see [6]), and they were discussed in the context of the photocatalytic H 2 O splitting in order to produce H 2 as a carrier of chemical energy (for photochemical H 2 O reduction, see [7]). However, relatively little is known about mononuclear complexes containing these metal centres in such formal oxidation states. Assuming that electron-withdrawing ligands should stabilize formally low metal-oxidation states, early work focused on the synthesis of the carbonyl species [M(CO) 4 ] and [M(CO) 4 ] À (M Rh, Ir). However, the paramagnetic d 9 -valence-electron-configured [M(CO) 4 ] complexes were only observed in inert-gas matrices at very low temperatures [8 ± 10]. On the other side, the colorless anionic d 10 -valence-electron-configured [M(CO) 4 ] À ions are quite stable and were

show abstract

Iridium carbonyl compounds from the reaction of Ir4(CO)12 with sodium

Cited by 27 publications

References 0 publications

Reactions of Laser-Ablated Co, Rh, and Ir with CO: Infrared Spectra and Density Functional Calculations of the Metal Carbonyl Molecules, Cations and Anions in Solid Neon

Reactions of Laser-Ablated Co, Rh, and Ir with CO: Infrared Spectra and Density Functional Calculations of the Metal Carbonyl Molecules, Cations and Anions in Solid Neon

An Unusual Carbonyl Chemical Shift in a Carbonylhexairidium Cluster: A Combined Solid‐State NMR and DFT Approach

Protonation and Hydrogenation Experiments with Iridium(0) and Iridium(−1) tropp Complexes: Formation of Hydrides

Contact Info

Product

Resources

About