32679-03-1

Usage

Reactions

Catalyst for synthesis of vinyl ethers from vinyl acetate and alcohols. Catalyst used for the complete hydrogenation of benzene at room temperature and mild pressures.

Upstream product

• 14104-20-2 silver tetrafluoroborate 
• 75-05-8 acetonitrile 
• 74238-34-9 [(1,5-cyclooctadiene)Ir(η6-benzene)]BF4 
• 12112-67-3 bis(1,5-cyclooctadiene)diiridium(I) dichloride 
• 13755-29-8 sodium tetrafluoroborate 

Downstream Products

• 290307-62-9 [(Ir(cod))2(μ-Cl)(μ-1-benzyl-2-imidazolyldiphenylphosphine)]BF4 
• 871505-46-3 cis-[Ir(cod)((diphenylphosphanyl)methanol)2]BF₄ 
• 1039636-68-4 iridium(I)(COD)bis(η1-2-phenyl-1,8-naphthyridine)(BF4) 
• 757959-77-6 Ir(1,5-cyclooctadiene)(tri(p-tolyl)phosphine)2BF₄ 
• 1239599-61-1 glyoxal-bis(2,4,6-trimethylphenylimine)(cycloocta-1,5-diene)iridium tetrafluoroborate 
• 1239599-63-3 glyoxal-bis(2,6-diisopropylphenylimine)(cycloocta-1,5-diene)iridium tetrafluoroborate 
• 87556-62-5 (1,5-cyclooctadiene)((diphenylphosphino)ethyl diphenylphosphinite)iridium(I) tetrafluoroborate*1/2CH2Cl2%(Ir(cod)(pop))BF4*1/2CH2Cl2 
• 87481-96-7 [1,2-bis(diphenylphosphino)-3-(4-(ethoxydimethylsilyl)phenoxy)propane][1,5-cyclooctadiene]iridium(I) tetrafluoroborate 

Relevant academic research and scientific papers

Carbon monoxide induced double cyclometalation at the iridium center

Bubbling of CO into a dichloromethane solution of [Ir(COD)(CH 3CN)2][BF4] followed by the addition of 2-phenyl-1,8-naphthyridine (LH) at room temperature results in the bis-cyclometalated IrIII complex [Ir(C^N) 2(CO)(LH)][BF4] (C^N = L). The observed cyclometalation contradicts the classical role of CO, which is to hinder oxidative addition by lowering electron density on the metal. DFT calculations reveal that the first cyclometalation involves oxidative addition of the ligand. Subsequently, preferential electrophilic activation of the second ligand followed by elimination of dihydrogen affords the bis-cyclometalated Ir III complex.

Complexes of Platinum Group Metals with a Conformationally Locked Scorpionate in a Metal-Organic Framework: An Unusually Close Apical Interaction of Palladium(II)

We report synthetic strategies for installing platinum group metals (PGMs: Pd, Rh, Ir, and Pt) on a scorpionate-derived linker (TpmC*) within a metal-organic framework (MOF), both by room-temperature postsynthetic metalation and by direct solvothermal synthesis, with a wide range of metal loadings relevant for fundamental studies and catalysis. In-depth studies for the palladium adduct Pd(II)@Zr-TpmC? by density-functional-theory-assisted extended X-ray absorption fine structure spectroscopy reveals that the rigid MOF lattice enforces a close Pd(II)-Napical interaction between the bidentate palladium complex and the third uncoordinated pyrazole arm of the TpmC? ligand (Pd-Napical = 2.501 ± 0.067 ?), an interaction that is wholly avoided in molecular palladium scorpionates.

Synthesis and Mode of Action Studies on Iridium(I)–NHC Anticancer Drug Candidates

We report the synthesis, characterization, and biological activity of IrI complexes with triazole- (NNHC) and thiazole-based (NSHC) N-heterocyclic carbene ligands. Starting from the dimeric [Ir(COD)Cl]2, we obtained complexes of composition Ir(COD)(NNHC)Cl (4a), Ir(COD)(NNHC)X (4b: X = Cl; 4bBr: X = Br), [Ir(COD)(NNHC)(NHC)]I (5a), [Ir(COD)(NSHC)2]Cl (6a), and [Ir(COD)(NSHC)(NNHC)]Cl (6b) by adaptation of established synthetic methods for metal–NHC complexes. Their interactions with model proteins cytochrome c and lysozyme, as well as with the oligonucleotide hexamer (CG)3 (ODN1), were studied. Although most complexes did not show any strong interactions with these biomolecules, all complexes were active against HT-29 and MCF-7 cancerous cells, with IC50 values ranging between 1 and 60 μm. The most active compounds were the cationic bis(carbene) derivatives 5 and 6. All compounds generated high levels of reactive oxygen species (ROS) after incubation for 48 h in MCF-7 cells, possibly suggesting a redox-mediated mechanism of action. Interestingly, there were distinctive differences in the superoxide/(total ROS) ratios induced by the different groups of compounds.

C–N Bond Coupling Reactions of Ammonia with Acetone Promoted by Iridium and Rhodium Complexes: Experimental and DFT Studies

Treatment of acetone solutions of the known chlorido-bridged complexes [{M(μ-Cl)(cod)}2] (M = Ir, Rh; cod = 1,5-cyclooctadiene) under an ammonia atmosphere afforded the cationic complexes {M(cod)[κN,κN-NH2–C(CH3)2–CH2–C(CH3)=NH]}Cl [M = Ir (3), Rh (4)]. The molecular structures of 3 and 4 showed the formation of six-membered metallacycles due to the presence of a 4-imino-2-methylpentan-2-amine-κN,κN-chelated ligand. Alternatively, the cations [M(cod)(NCCH3)2]BF4(M = Ir, Rh) reacted with gaseous ammonia at atmospheric pressure affording bis(ammine) complexes [M(cod)(NH3)2]BF4[M = Ir (5), Rh (6)], which were found to react with acetone, forming cations [M(cod)(κN,κN-NH2–C(CH3)2–CH2–C(CH3)=NH)]BF4[M = Ir (7), Rh (8)]. DFT studies reveal that the transformation of 6 into 8 is mediated by NH3molecules acting as an external base. The reaction is triggered by deprotonation of an ammonia ligand forming a amido–metal intermediate, which further transforms into an acetimino ligand through aldol condensation. The terminal methyl group of one acetimino ligand is deprotonated by NH3yielding an enamine ligand, which can react with the imine ligand through concerted nucleophilic addition to afford the metallacycle, which is stabilized by protonation.

Arene transition-metal chemistry. 5. Arene ligand exchange and reactivity in η6-arene iridium(I) complexes

The arene-exchange behavior of a number of arene complexes of the type [Ir(η6-arene)(η4-c-1,5-C8H 12)+](X-) was examined in acetone and chloroform solution. In acetone, the reaction [Ir(η6-arene)(η4-c-1,5-C8H 12)+](BF4-) + arene′ = [Ir(η6-arene′)(η4-c-1,5-C8H 12)+](BF4-) + arene proceeded via solvent displacement of coordinated arene to yield a spectroscopically observable intermediate, [Ir(η4-c-1,5-C8H12)(acetone) x]+, which subsequently reacted with arene′ to form the new arene′ complex. The rate of exchange was independent of arene′ concentration and the extent of methyl substitution on arene′ while it was dependent on the extent of methyl substitution of the initially coordinated arene. Competitive exchange reactions established that the rate of exchange was independent of the stereochemistry of methyl substitution if the incoming arene had three or fewer methyl substituents. However, for more highly substituted arenes, a steric effect was operative; the 1,2,3,4-C6H2(CH3)4 complex was the preferred kinetic product in competitive exchanges between 1,2,3,4-C6H2(CH3)4 and 1,2,3,5-C6H2(CH3)4, 1,2,4,5-C6H2(CH3)4, or C6(CH3)6. Arene exchange proceeded much more slowly in chloroform than in acetone and was anion dependent. Equilibrium constants for a number of arene-exchange reactions were measured. In accord with literature data for other transition-metal complexes, the stabilities of the iridium arene complexes were independent of the stereochemistry of methyl substitution and increased with increasing methyl substitution on the arene ring.