(chloro)bis(2'-para-tolylpyridinato-N,C(2'))(pyrazole)iridium(III) | 710278-62-9

• 英文名称: (chloro)bis(2'-para-tolylpyridinato-N,C(2'))(pyrazole)iridium(III)
• CAS: 710278-62-9
• 化学式: C₂₇H₂₄ClIrN₄
• 分子量: 632.187
• InChiKey: WAMXKMSYEXJOCE-UHFFFAOYSA-M

反应信息

• 作为产物：
  描述：

  吡唑 、 [{Ir(μ-Cl)(2-(p-tolyl)pyridinato)₂}₂] 以 二氯甲烷 为溶剂， 以80%的产率得到(chloro)bis(2'-para-tolylpyridinato-N,C(2'))(pyrazole)iridium(III)
  参考文献：
  名称：

  Synthesis and characterization of cyclometalated Ir(III) complexes with pyrazolyl ancillary ligands

  摘要：

  The syntheses and structures of a series of (N,C-2'-(2-para-tolyipyridine))(2)Ir(LX) [(tpy)(2)Ir(LX)] and (N,C-2'-(4',6'-difluorophenylpyridine))(2)Ir(LX) [(dfppy)(2)Ir(LX)] are reported, where LX are pyrazolyl and pyrazolyl-borate ligands. Reaction of the dichloro-bridged dimer [(tpy)(2)Ir(mu-Cl)]2 with excess pyrazolyl-borate ligands forms a protonated-dipyrazolyl Ir complex, (tpy)(2)Ir(pz(2)H). The Ir bound chloride in [(tpy)(2)Ir(mu-Cl)](2) presumably facilitates the hydrolysis of pyrazolyl-borate. Thus, the syntheses of Ir complexes with bis(pyrazolyl)borates, e.g., (tpy)(2)Ir(pz(2)Bpz(2)) and (tpy)(2)Ir(pz(2)BEt(2)) require the chloride abstraction by CF3SO3Ag before pyrazolyl-borate is added to the reaction solution. (tpy)(2)Ir(pz(2)H), (tpy)(2)Ir(pzH)(2)(CF3SO3) (tpy)(2)Ir(pz(2)Bpz(2)) and (tpy)(2)Ir(pz(2)BEt(2)) have been structurally characterized by X-ray crystallography. The two pyrazolyl rings of (tpy)(2)Ir(pz(2)H) are nearly coplanar (dihedral angle, 12degrees), due to the presence of N-H...N hydrogen bond (N...N distance of 2.56 Angstrom), while the two pyrazolyl rings of (tpy)(2)Ir(pzH)(2)(CF3SO3) are not coplanar (pz-pz dihedral angle, 47degrees). Unlike other eta(2)-pyrazolyl-borate complexes, the (tpy)(2)Ir(pz(2)BEt(2)) exhibits a rare quasi-chair conformation adopted by Ir-N-N-B-N-N the ring, rather than the more common boat conformations which have been observed previously. Similarly, the Ir-N-N-B-N-N cycle of (tpy)(2)Ir(pz(2)Bpz(2)) adopts a half-chair conformation, more flattened than the typical boat conformation. While the choice of pyrazolyl-borate ligand does not change the structural properties of the "(tpy)(2)Ir" fragment, it markedly affects the photophysical properties of both (tpy)(2)Ir(pz(2)BR(2)) and (dfppy)(2)Ir(pz(2)BR(2)) complexes. The pyrazolyl-borate ancillary ligands affect the absorption and emission energies of these complexes by tuning the HOMO (highest occupied molecular orbital) energies. The electron-withdrawing ancillary ligands, e.g., pz(2)Bpz(2) decrease the electron density on the iridium, stabilizing the metal-centered HOMOs. (C) 2003 Elsevier Ltd. All rights reserved.

  DOI：

  10.1016/j.poly.2003.11.028