Os3(CO)10(2,3-dipyrid-2-ylpyrazine) | 209162-06-1

• 英文名称: Os3(CO)10(2,3-dipyrid-2-ylpyrazine)
• CAS: 209162-06-1；202661-35-6；202756-16-9；172098-23-6
• 化学式: C₂₄H₁₀N₄O₁₀Os₃
• 分子量: 1084.96
• InChiKey: NWVUMGQMXGQHHC-UHFFFAOYSA-N

计算性质

• 辛醇/水分配系数(LogP)：
  None
• 重原子数：
  None
• 可旋转键数：
  None
• 环数：
  None
• sp3杂化的碳原子比例：
  None
• 拓扑面积：
  None
• 氢给体数：
  None
• 氢受体数：
  None

反应信息

• 作为反应物：
  描述：

  2-甲基四氢呋喃 、 Os3(CO)10(2,3-dipyrid-2-ylpyrazine) 以 2-甲基四氢呋喃 为溶剂， 生成 Os(-)(CO)4-Os(CO)4-Os(+)(CO)2(2-methyltetrahydrofuran)(2,3-dipyrid-2-ylpyrazine)
  参考文献：
  名称：

  Photochemistry of the Clusters Os3(CO)10(L) (L = 2,2'-Bipyridine, 2,2'-Bipyrimidine, 2,3-Dipyrid-2-ylpyrazine, 2,3-Dipyrid-2-ylbenzoquinoxaline). Reversible Opening of an Os-Os Bond with Formation of a Zwitterion

  摘要：

  The complexes Os-3(CO)(10)(L)(L = 2,2'bipyridine (bpy), 2,2'-bipyrimidine (bpym), 2,3-dipyrid-2-ylpyrazine (dpp), and 2,3-dipyrid-2-ylbenzoquinoxaline (dpb)) were synthesized, and their low-energy Os --> L (MLCT) transitions were characterized with resonance Raman spectroscopy. Continuous wave excitation into the MLCT transitions does not lead to product formation. However, rapid-scan TR and nano- and picosecond time-resolved absorption spectra show the formation of a transient species (for L = bpy, bpym, and dpp) which reacts back to give the parent complex. In toluene the transient has a lifetime of less than in nr and is assigned to an MLCT state of the cluster. In coordinating solvents a different transient species is observed with a lifetime that strongly depends on the coordinating ability of the solvent and the basic properties of L (200-900 ns in tetrahydrofuran (THF), 5-20 s in CH3CN). The transient species could even be obtained as a stable photoproduct by reaction in 2-MeTHF at 113 K and upon irradiation at room temperature in the presence of a halide salt, The transient species is proposed to be the zwitterion Os-(CO)(4)-Os(CO)(4)-Os+(CO)(2)(S)(L). The positive charge of the metal in the Os+(CO)(2)(S)(L) moiety is evident from the Raman and H-1-NMR spectral the coordination of the solvent from its large influence on the lifetime, and the absorption maximum of the transient intermediate, Since the zwitterion. is already formed within 50 ps after the laser pulse, it is most probably produced by reaction from the MLCT state(s). A coordinating solvent molecule may initiate this reaction by coordination to the metal center of the Os(CO)(2)(alpha-diimine) fragment in its MLCT state. The extra negative charge donated by the solvent may then cause a heterolytic splitting of an Os-Os bond with formation of thp zwitterion.

  DOI：

  10.1021/ic00129a016
• 作为产物：
  描述：

  bis(acetonitrile)decacarbonyltriosmium 、 2,3-二(2-吡啶基)吡嗪 以 二氯甲烷 为溶剂， 以84%的产率得到Os3(CO)10(2,3-dipyrid-2-ylpyrazine)
  参考文献：
  名称：

  两种异构产物[O的3（μ-H）（C 14 H ^ 9 Ñ 4）（CO）9 ]由群集的orthometallation [O的形成3（C 14 H ^ 10 Ñ 4）（CO）10 ]含有螯合配位体2,3-双（2-吡啶基）吡嗪

  摘要：

  不稳定化合物的治疗[O的3（CO）10（CH 3 CN）2 ]与2,3-二（2-吡啶基）吡嗪（C 14 ħ 10 Ñ 4）在室温下二氯甲烷洗脱簇[O的3（C 14 H ^ 10 ñ 4）（CO）10 ] （1） ，其中包含螯合配体协调轴向通过吡啶环中的一个和平展通过同时吡啶环中的一个的吡嗪氮原子保持不协调。热解1所导致CO和收率两个结构异构体[Os中损失3（μ-H）（μ，η 3 -C 14 ħ 9 Ñ 4）（CO）9 ] （2）和（3） 。异构体2包含一个orthometallated 2-吡啶基和未orthometallated一个协调2-吡啶基。七元螯合环形成和吡嗪环是不协调的。在另一方面，异构体3包含在吡嗪环金属化，以形成与所述一个吡啶环其余不协调一个五元螯合环2-吡啶-1,4-吡嗪片段。的分子结构1 - 3通过X射线晶体学研究证实。

  DOI：

  10.1016/j.jorganchem.2004.10.009

文献信息

• Photochemistry of the Triangular Clusters Os₃(CO)₁₀(α-diimine): Homolysis of an Os−Os Bond and Solvent-Dependent Formation of Biradicals and Zwitterions
  作者：Jos Nijhoff、Maarten J. Bakker、František Hartl、Derk J. Stufkens、Fu、Rudi van Eldik

  DOI：10.1021/ic9707319

  日期：1998.2.23

  Several clusters Os-3(CO)(10)(alpha-diimine) (alpha-diimine = pyridine-2-carbaldehyde N-R-imine or 1,4-di-R-1,4-diazabutadiene) were synthesized and studied with respect to their spectroscopic and photochemical properties. According to the resonance Raman spectra the visible absorption band of these clusters belongs to electronic transitions having Os-to-a-diimine charge transfer (MLCT) character with a variable degree of pi-delocalization within the Os(alpha-diimine) moiety. Upon irradiation into these transitions zwitterions Os-(CO)(4)-Os(CO)(4)-Os+-(S)(CO)(2)(alpha-diimine) are formed in coordinating solvents (S) and biradicals *Os(CO)(4)-Os(CO)(4)-Os+(CO)(2)(alpha-diamine(.-)) in noncoordinating solvents and in THF at ambient temperature. The zwitterions live seconds in nitrile solvents and minutes in pyridine, and they largely regenerate the parent clusters. Quantum yields of zwitterion formation are wavelength independent and range from 10(-2) to 3 x 10(-2) with an activation energy varying from 440 to 720 cm(-1). For one of the clusters the quantum yield of zwitterion formation in pyridine was studied in dependence of applied pressure. The activation volume Delta V-double dagger = +7.0 +/- 0.5 cm(3) mol(-1) derived from these measurements indicates that the effect of bond cleavage is partially offset by coordination of the solvent. In apolar solvents biradicals are formed instead of zwitterions, which could be detected with nanosecond time-resolved absorption spectroscopy, while their adducts with nitrosodurene were observed with EPR spectroscopy. Their lifetimes vary from 5 ns to 1 mu s depending on the solvent and the alpha-diimine. The biradicals transform into zwitterions in the presence of a Lewis base. in addition, they produce with low efficiency an isomeric product in which the cr-diimine bridges between two Os atoms. The formation of very similar photoproducts (biradicals, cr-diimine-bridged isomeric products, charge-separated species) as in the case of binuclear metal-metal-bonded complexes such as (CO)(5)MnMn(CO)(3)(alpha-diimine) points to the occurrence of a primary photoprocess in which an Os-Os bond is broken homolytically. This reaction most likely occurs from a reactive (3) sigma pi* state after surface crossing from the unreactive but optically accessible MLCT states.