94249-80-6

Upstream product

• 89529-62-4 dihydridobis(acetone)bis(tris(p-fluorophenyl)phosphine)iridium(III) hexafluoroantimonate 
• 110-83-8 cyclohexene 
• 110077-68-4 {IrH₂(acetone)2(PPh₃)2}SbF₆ 
• 558-37-2 tert-butylethylene 
• 110-82-7 cyclohexane 
• 91410-24-1 {(η5-cyclohexadienyl)IrH(PPh3)2}SbF6 
• 287-92-3 Cyclopentane 

Downstream Products

• 94345-85-4 IrH₂(CH₃CN)2(P(C₆H₅)3)2⁽¹⁺⁾*SbF₆^(1-) = [IrH₂(CH₃CN)2(P(C₆H₅)3)2]SbF₆ 
• 91410-27-4 {Ir(COD)(PPh₃)2}SbF₆ 
• 110077-68-4 {IrH₂(acetone)2(PPh₃)2}SbF₆ 

Relevant academic research and scientific papers

Dehydrogenation of alkanes to arenes by iridium complexes

Dehydrogenation of cyclohexanes to arenes using [IrH2(Me2CO)2(PAr3) 2]SbF6 without a solvent is described. The chlorinated solvents previously used for reactions of this type are shown to transfer chloride to the metal to give chloro-bridged binuclear species. P-C bond cleavage in the phosphines limits the efficiency of the alkane reactions, which seem to involve the interface between the crystal of iridium complex and the alkane. Their yield is found to be strongly dependent on the counterion used, SbF6 being the best we have tried.

Arene and cyclohexadienyl complexes as intermediates in the selective catalytic dehydrogenation of cyclohexenes to arenes

A catalytic aromatization of cyclohexene to benzene is described by using [IrH2(Me2CO)2L2]SbF6 (L = PPh3) as catalyst in refluxing 1,2-C2H4Cl2. tert-Butylethylene (tbe) acts as hydrogen acceptor; in the absence of tbe, 2 equiv of cyclohexane are formed per mole of benzene. A mechanism is suggested based on the isolation of the proposed intermediates [Ir(η5-C6H7)HL2]SbF6 and [Ir(η6-C6H6)L2]SbF6. Some reactions of these complexes are discussed.

Haptotropic rearrangements and C-H bond activation in indan, indenyl, and naphthalene complexes of iridium

2-Vinylnaphthalene reacts with [IrH2(Me2CO)2L2]A (1, L = PPh3, A = SbF6) to give [Ir(NpEt)L2]A (3, NpEt = 2-ethylnaphthalene). Below 10°C the kinetic product has the metal bound to the ring bearing the ethyl group. Above 10°C a 50:50 mixture of haptomers is formed in each of which the metal is bound to a different ring. Indene reacts with 1 at 25°C to give [Ir(η6-indan)L2] A (4), but at 80°C, 4 dehydrogenates to give [Ir(η5-indenyl)HL32]A (5). Indan reacts with 1 and tert-butylethylene (tbe) at 90°C to give first 4 and then 5, an example of arene precoordination facilitating CH activation on the side chain. 3, 4, and 5 as well as the related [Ir(η5-C6H7)HL2]A all react with tbe and cyclopentane at 100°C to give [IrCpHL2]A, all examples of alkane C-H activation. The conformation of the idenyl ring in 5, deduced from NMR measurements, puts H trans to the fused benzene ring, contradicting the expectation based on steric effects. A rationalization is proposed that also embraces other literature examples. 5 has largely 18-electron character with an η5-indenyl and is chemically rather inert, but 3 has largely 16-electron character with an η4-NpEt ligand and is chemically very reactive. 13C NMR was used to determine the hapticity of the carbocyclic ligands.