(triphos)Ir(η4-benzene)(BPh4) | 135006-00-7

• 英文名称: (triphos)Ir(η4-benzene)(BPh4)
• CAS: 135006-00-7
• 化学式: C₂₄H₂₀B*C₄₇H₄₅IrP₃
• 分子量: 1214.25
• InChiKey: PEEFYBRGLBICKE-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
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• 重原子数：
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• 可旋转键数：
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• 环数：
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• sp3杂化的碳原子比例：
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• 拓扑面积：
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• 氢给体数：
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• 氢受体数：
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反应信息

• 作为反应物：
  描述：

  (triphos)Ir(η4-benzene)(BPh4) 、 苯并噻吩 以 neat (no solvent, solid phase) 为溶剂， 以100%的产率得到{(triphos)Ir(η2-C,S-C8H6S)}BPh4*1.5THF*0.5EtOH
  参考文献：
  名称：

  Hydrodesulfurization model systems. Homogeneous and heterogeneous (solid-gas) hydrogenation of benzothiophene at iridium

  摘要：

  DOI：

  10.1021/ja00069a061
• 作为产物：
  描述：

  、 乙炔 以 neat (no solvent) 为溶剂， 生成 (triphos)Ir(η4-benzene)(BPh4)
  参考文献：
  名称：

  Molecular Solid-Gas Organometallic Chemistry. Catalytic and Stoichiometric Iridium-Assisted C-C Bond-Forming Reactions Involving Ethyne and Ethene

  摘要：

  Treatment of crystals of the (eta2-ethene)dihydride complex [(triphos)Ir(H)2(C2H4)]BPh4 (1; triphos = MeC(CH2PPh2)3) with ethyne (4 atm) at 70-degrees-C for 3 h results in evolution of ethene and but-2-ene and formation of five different organometallic products, namely the eta4-benzene complex [(triphos)Ir(eta4-C6H6)]BPh4 (2), the eta4-buta-1,3-diene complex [(triphos)Ir(eta4-C4H6)]BPh4 (3), the eta4-cyclohexa-1,3-diene complex [(triphos)Ir(eta4-C6H8)]BPh4 (4), and the crotyl hydride isomers [(triphos)Ir(H) (eta3-MeC3H4)]BPh4 (5-anti and 5-syn) in a kinetic product ratio of 35:5:23:28:9. At 100-degrees-C, the solid-gas reaction produces catalytic amounts of benzene, the catalyst precursor being the eta4-benzene complex 2. Temperature-programmed reactions carried out in a flow reactor and the use of isolated complexes in independent solid-gas reactions permit mechanistic conclusions which account for the varied organic and organometallic products. The ethene ligand in 1 is an essential ingredient for both cyclotrimerization and cooligomerization reactions of ethyne, which are traversed by eta3-crotyl complexes. Conversely, the ethene ligand is a competitive inhibitor for the reductive dimerization of ethyne to buta-1,3-diene, for which the two hydride ligands are mandatory. Comparison with fluid solution-phase systems provides evidence for the control exerted by the constraining environment of the crystal lattice on the solid-gas reactions.

  DOI：

  10.1021/om00016a020

文献信息

• Thiophene C–S bond cleavage by rhodium and iridium. An unprecedented bridging mode of the open C₄H₄S fragment
  作者：Alessia Bacchi、Claudio Bianchini、Verónica Herrera、M. Victoria Jiménez、Carlo Mealli、Andrea Meli、Simonetta Moneti、Maurizio Peruzzini、Roberto A. Sánchez-Delgado、Francesco Vizza

  DOI：10.1039/c39950000921

  日期：——

  The complexes [(triphos)M}2(µ-η3,η4-SC4H4)](Y)2(M = Ir, Y = BPh4; M = Rh, Y = PF6) are obtained by reaction of thiophene with either [(triphos)Ir(η4-C6H6)]BPh4 in Me2SO at 80 °C or [(triphos)RhCl(C2H4)]+ TIPF6 in THF at room temperature; a single-crystal X-ray diffraction analysis of the iridium complex shows that an open C4H4S moiety sits astride two metal centres; the bridge-bonding mode implies the sharing of four electron pairs with the metals.

  配合物 [(triphos)M}2(µ-β3,β4-SC4H4)](Y)2(M = Ir, Y = BPh4; M = Rh, Y = PF6) 通过以下反应获得噻吩与 [(triphos)Ir(δ4-C6H6)]BPh4 在 Me2SO 中于 80 °C 或[(triphos)RhCl(C2H4)]+ TIPF6 在 THF 中，室温；铱配合物的单晶 X 射线衍射分析表明，开放的 C4H4S 部分横跨两个金属中心；桥键模式意味着与金属共享四个电子对。
• HDS Model Systems. Coordination, Opening, and Hydrogenation of Benzo[b]thiophene at Iridium
  作者：Claudio Bianchini、Andrea Meli、Maurizio Peruzzini、Francesco Vizza、Simonetta Moneti、Veronica Herrera、Roberto A. Sanchez-Delgado

  DOI：10.1021/ja00089a027

  日期：1994.5

  The eta 4-benzene complexes [(triphos)Ir(C6H6)]Y (Y = BPh(4), 1a; PF6, 1b) react with benzo[b]thiophene (BT) at room temperature to give the unprecedented [(triphos)Ir(eta(3)-C,C,S-C8H6S)]Y (Y = BPh(4), 2a; PF6, 2b) in which intact BT is coordinated to the metal center through the S atom and the C-2=C-3 bond. 2a and 2b are transformed upon mild thermolysis into the iridabenzothiabenzene complexes [(triphos)Ir(eta(2)-C,S-C8H6S)]Y (Y = BPh(4), 3a; PF6, 3b). An X-ray analysis has been carried out on 3a.1.5THF.0.5EtOH. The coordination geometry around iridium may be described as a distorted trigonal-bipyramid, the metal center being surrounded by the three phosphorus atoms of triphos and by a carbon and a sulfur atom from a CS-cleaved BT molecule. Crystal data: triclinic, space group P (1) over bar, a 17.391(3) Angstrom, b = 16.957(4) Angstrom, c = 12.795(3) Angstrom, alpha = 77.51(2)degrees, beta = 80.98(2)degrees, gamma = 75.50(2)degrees, Z = 2, d(calcd) = 1.31 g cm(-3), n(obsd) = 7636, R = 0.072. Interaction of 2a with CO (1 atm, 20 degrees C) yields [(triphos)Ir(CO)(2)]BPh(4) (4) plus free BT, whereas 3a requires more drastic conditions (5 atm, 70 degrees C) to eliminate BT and produce 4. 2a also reacts with H-2 (1 atm, 20 degrees C) to produce [(triphos)Ir(H)(2)(eta(1)-S-BT)]BPh(4) (5), which can be independently prepared by treatment of [(triphos)Ir(H)(2)(THF)]BPh(4) with BT; at 5 atm H-2, free BT is obtained together with [(triphos)Ir(H)(3)], BPh(3), and benzene, as a result of a heterolytic splitting of H-2 at the [(triphos)Ir(H)(2)](+) fragment assisted by the BPh(4)(-), counteranion. The C-S-cleaved BT in 3a is readily hydrogenated (5 atm, 20 degrees C) to 2-ethylbenzenethiolate, producing [(triphos)Ir(H)(2)o-S-(C6H4)C2H5}] (8) plus BPh(3) and benzene also via heterolytic splitting of H-2 assisted by BPh(4)(-), protonolysis of 8 with 2 equiv HCl produces (triphos)IrCl3 with concomitant liberation of 2-ethylbenzenethiol, a primary product of BT HDS. If the PF6- analogue 3b is used instead, the reaction with H-2 under identical conditions yields the thiolate-bridged dimer [(triphos)IrHmu-o-S(C6H4)C2H5}2HIr(triphos)](PF6)(2) (9b). 3a also reacts with LiHBEt(3) to give [(triphos)Ir(H)(eta(2)-C,S-C8H6S)] (11), which converts in THF solution at 66 degrees C into [(triphos)Ir(eta(3)-S(C6H4)CH=CH2)] (12) by hydride migration to C-2; neither 11 nor 12 react with H-2 under mild conditions. Addition of HBF4.OEt(2) to 12 yields [(triphos)Ir(eta(4)-S(C6H4)C(H)Me)]BF4 (13c), which does react with H-2 even at 1 atm to give the thiolate-bridged dimer [(triphos)IrHmu-o-S(C6H4)C2H5}2HIr(triphos)](BF4)(2) (9c). 13c also reacts with H- to give [(triphos)IrH(eta(2)-S(C6H4)C(H)Me)] (14), which in turn reacts with H-2 and HBF4.OEt(2) to yield 8 and 9c, respectively.
• Bianchini, Claudio; Caulton, Kenneth G.; Foltng, Kirsten, Journal of the American Chemical Society, 1992, vol. 114, # 18, p. 7290 - 7291
  作者：Bianchini, Claudio、Caulton, Kenneth G.、Foltng, Kirsten、Meli, Andrea、Peruzzini, Maurizio、Polo, Alfonso、Vizza, Francesco

  DOI：——

  日期：——
• The Mechanism of Acetylene Cyclotrimerization Catalyzed by the fac-IrP3+ Fragment: The Relationship between Fluxionality and Catalysis
  作者：Claudio Bianchini、Kenneth G. Caulton、Catherine Chardon、Marie-Liesse Doublet、Odile Eisenstein、Sarah A. Jackson、Todd J. Johnson、Andrea Meli、Maurizio Peruzzini

  DOI：10.1021/om00017a067

  日期：1994.5

  Reaction of [(triphos)Ir(C2H4)2](BPh4) with C2H2 at 25-degrees-C gives [(triphos)Ir(eta4-C6H6)](BPh4), 1, which was shown to have this Ir/benzene connectivity by single crystal X-ray diffraction. Crystal data (-155-degrees-C): a = 16.471(6) angstrom, b = 17.126(6) angstrom, c = 12.030(4) angstrom, alpha = 101.22(2)-degrees, beta = 93.61(2)-degrees, and gamma = 75.46(1)-degrees with Z = 2 in space group Pi. This species reacts with C2H2 in the presence of Cl- to give (triphos)IrCl(eta2-C4H4), 2, which can be converted back to 1 with C2H2 in the presence of the chloride scavenger TlPF6. Ethyne will displace C6H6 from 1 at 60-degrees-C in THF, thus completing a catalytic cyclotrimerization of C2H2 to benzene. While the phosphorus nuclei in 1 form an AM2 spin system, these undergo site exchange with activation parameters DELTAH = 10.7(3) kcal/mol and DELTAS = -9.5(6) kcal-1 mol-1. The benzene ring H-1 NMR spectra are also temperature-dependent, and the fluxionality can be accounted for by the same activation parameters appropriate to P-31 site exchange; the same physical mechanism thus accomplishes both site exchanges. The structural study indicates that eta4-C6H6, which is nonplanar, is a stronger pi-acceptor than is butadiene itself. A multistep mechanism has been studied with extended Huckel calculations. It is shown that the C-C bond formation between the first two alkynes to give the unsaturated metallacyclopentadiene is permitted when the three spectator ligands are in a fac geometry but is forbidden when they are in a mer geometry, which explains the puzzling difference of reactivity between monodentate triphosphine and tripodal complexes. It is shown that this unsaturated metallacycle is highly reactive toward an incoming ligand since it is not strongly stabilized by conjugation within the pi system. This explains why it can be isolated by trapping with a Lewis base. The addition of the third alkyne to the metallacyclopentadiene, leading to the eta4-benzene complex, can be achieved in a concerted manner and leads directly to the product. The C-C bond lengths within the eta4-benzene are shown to be due to the presence of a potent metal donor and to the nonplanarity of the benzene ring. The fluxionality of the eta4-benzene, which makes all carbons of the ring and the three phosphine ligands equivalent on the NMR time scale, is suggested to be due to an easy displacement/rotation of the IrP3+ fragment around the ring. This displacement avoids eta6-coordination (20-electron species) but passes through unsaturated eta3- and eta2-benzene coordination modes. These unsaturated species (notably the eta2 one) have the proper low-lying LUMO to coordinate an additional alkyne. This leads back to the monoalkyne complex and benzene production. Fluxionality and reactivity of the eta4-benzene ring are therefore interrelated. The efficiency of the catalysis is suggested to be due to the fact that all intermediates are reactive 16-electron species stabilized by additional donation from the conjugated pi system of the organic ligand. The presence of an enforced fac arrangement of the three spectator ligands avoids the thermodynamic trap of the trigonal bipyramidal bis(alkyne) complex.
• Molecular solid-gas organometallic chemistry. Catalytic and stoichiometric transformations of ethyne at iridium
  作者：Claudio Bianchini、Piero Frediani、Mauro Graziani、Jan Kaspar、Andrea Meli、Maurizio Peruzzini、Francesco Vizza

  DOI：10.1021/om00032a006

  日期：1993.8

  The eta2-ethene dihydride [(triphos)Ir(H)2-(C2H4)]BPh4 (1; triphos = MeC(CH2PPh2)3) reacts in the solid state with ethyne (4 atm) at 70-degrees-C to give five different organometallic products, namely [(triphos)-Ir(eta4-C6H6)]BPh4 (2), [(triphos)Ir(eta4-C6H8)]BPh4 (3), [(triphos)Ir(eta4-C4H6)]BPh4 (4), [(triphos)Ir(H)(eta3-MeC3H4)]BPh4 (5-anti), and [(triphos)Ir(H)(eta3-MeC3H4V-BPh4 (5-syn), and but-2-ene. At 100-degrees-C, the solid-gas reaction produces catalytic amounts of benzene, the real catalyst being the eta4-benzene complex 2. Comparison with fluid solution systems provides evidence for the control exerted by the constraining environment of the crystal lattice of the organometallic complex on the reaction.