manganese(2+);dibromide;dihydrate | 13782-29-1

• 分子结构分类: 无机化合物 - 混合金属/非金属化合物 - 过渡金属盐
• 英文名称: manganese(2+);dibromide;dihydrate
• CAS: 13782-29-1
• 化学式: Br₂H₄MnO₂
• 分子量: 250.777
• InChiKey: QRXZGBXGSSMDTL-UHFFFAOYSA-L

计算性质

• 辛醇/水分配系数(LogP)：
  0.04
• 重原子数：
  5
• 可旋转键数：
  0
• 环数：
  0.0
• sp3杂化的碳原子比例：
  0.0
• 拓扑面积：
  2
• 氢给体数：
  2
• 氢受体数：
  2

反应信息

• 作为产物：
  描述：

  manganese(II) bromide tetrahydrate 以 水 为溶剂， 生成 manganese(2+);dibromide;dihydrate
  参考文献：
  名称：

  The Structure of the Homogeneous Oxidation Catalyst, Mn(II)(Br^-1)_x, in Supercritical Water:  An X-ray Absorption Fine-Structure Study

  摘要：

  Extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) spectroscopies were used to probe the first-shell coordination structure about Mn(II) and Br-1 ions that exist as contact ion pairs in supercritical water. This work was performed to clarify why solutions of MnBr2 in supercritical water are known to effectively catalyze the aerobic oxidative synthesis of terephthalic acid from p-xylene as well as a number of other methylaromatic compounds. The Mn and Br K-edge spectra were collected at the bending magnet beamline (sector 20) at the Advanced Photon Source, Argonne National Laboratory. The first-shell coordination structure about the Mn(II) ion changes from octahedral at ambient conditions to tetrahedral at supercritical conditions. Under supercritical conditions, the measured bond distances of Mn-OH2 and Mn-Br are 2.14 and 2.46 angstrom, respectively. Direct contact ion pairs form with about 2 Br-1 ions present in the first coordination shell of the Mn(II) ion. The structure of dissolved MnBr2, below 1.0 m, changes from essentially [Mn(II)(H2O)(6)](+2) to [Mn(II)(H2O)(2)(Br-1)(2)] in supercritical water (scH(2)O). When an excess of Br-1 ion is added, the bromide coordination number increases and the number of water molecules decreases. The results show that the initial MnBr2 catalyst in scH(2)O is tetrahedral with two Mn-Br contact ion pairs. The presence of the acetate anion deactivates the catalyst by formation of insoluble MnO.

  DOI：

  10.1021/ja053421v