trimethylborate | 3349-42-6

• 分子结构分类: 有机化合物 - 有机氧化合物 - 有机含氧阴离子化合物
• 英文名称: trimethylborate
• 英文别名: [¹¹B]boric acid trimethyl ester；Trimethylborat；trimethyl borate
• CAS: 3349-42-6
• 化学式: C₃H₉BO₃
• 分子量: 104.103
• InChiKey: WRECIMRULFAWHA-BMNHDCLUSA-N

物化性质

• 熔点：
  −34 °C(lit.)
• 沸点：
  68-69 °C(lit.)
• 密度：
  0.924 g/mL at 25 °C(lit.)
• 闪点：
  17 °F

计算性质

• 辛醇/水分配系数(LogP)：
  -0.09
• 重原子数：
  7
• 可旋转键数：
  3
• 环数：
  0.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  27.7
• 氢给体数：
  0
• 氢受体数：
  3

安全信息

• 危险品标志：
  Xn,F
• 安全说明：
  S16,S26,S36
• 危险类别码：
  R20/21/22,R36/37/38,R11
• 危险品运输编号：
  UN 2416 3/PG 2

反应信息

• 作为反应物：
  描述：

  trimethylborate 、 sodium hydride 以 neat (no solvent) 为溶剂， 生成 sodium borohydride
  参考文献：
  名称：

  储氢材料：硼烷氨络合物的结构和动力学

  摘要：

  这 激活根据电子结构理论对低温正交晶氨硼烷中的旋转能量进行了分析和表征。绝望的11乙合成富硼硼烷11 BD 3 ND 3，并从中精制结构中子粉末衍射 175 K时的数据。该温度已被选作先前报道的范围的中值 核磁共振波谱测量这些旋转。代表性分子簇 模型是从精炼的几何体组装而成的， 激活通过分析控制旋转动力学的环境因素来计算和表征能量。NH 3独立旋转的屏障，Ë一= 12.7 kJ mol -1，很大程度上取决于固态几何结构中的分子构象扭转。BH 3独立旋转的障碍，Ë一= 38.3 kJ mol -1，是分子扭转和大斥力分子间作用的总和氢–氢互动。但是，Ë一对于内部相关的旋转和保留的分子构象，计算出= 31.1 kJ mol -1。对障碍物高度和相应的旋转路径的分析表明，BH 3的旋转 团体涉及分子的NH 3末端的强烈相关的旋转。该观察结果表明，先前报道的BH 3旋转测量的障碍对应于H 3 B–NH

  DOI：

  10.1039/b718138h
• 作为产物：
  描述：

  甲醇 、 硼酸-11B 以 甲醇 为溶剂， 生成 trimethylborate
  参考文献：
  名称：

  储氢材料：硼烷氨络合物的结构和动力学

  摘要：

  这 激活根据电子结构理论对低温正交晶氨硼烷中的旋转能量进行了分析和表征。绝望的11乙合成富硼硼烷11 BD 3 ND 3，并从中精制结构中子粉末衍射 175 K时的数据。该温度已被选作先前报道的范围的中值 核磁共振波谱测量这些旋转。代表性分子簇 模型是从精炼的几何体组装而成的， 激活通过分析控制旋转动力学的环境因素来计算和表征能量。NH 3独立旋转的屏障，Ë一= 12.7 kJ mol -1，很大程度上取决于固态几何结构中的分子构象扭转。BH 3独立旋转的障碍，Ë一= 38.3 kJ mol -1，是分子扭转和大斥力分子间作用的总和氢–氢互动。但是，Ë一对于内部相关的旋转和保留的分子构象，计算出= 31.1 kJ mol -1。对障碍物高度和相应的旋转路径的分析表明，BH 3的旋转 团体涉及分子的NH 3末端的强烈相关的旋转。该观察结果表明，先前报道的BH 3旋转测量的障碍对应于H 3 B–NH

  DOI：

  10.1039/b718138h
• 作为试剂：
  描述：

  2-(3-bromophenyl)-1,3-dioxolane-2-d 在 正丁基锂 、 trimethylborate 作用下， 以 四氢呋喃 、 正己烷 为溶剂， 反应 28.0h， 以60%的产率得到
  参考文献：
  名称：

  Regiochemical Tagging:  A New Tool for Structural Characterization of Isomeric Components in Combinatorial Mixtures

  摘要：

  In this contribution we present a new combined synthetic and analytical strategy (regiochemical ragging) that allows facile determination of complete structure, including substituent position and regiochemistry, of mass-redundant components in complex combinatorial mixtures. The libraries of components (oxime ethers) are formed by the reaction of a mixture of substituents (aldehydes) with a scaffold containing several chemically similar attachment points (aminooxy groups), The structure of the resulting library components can then be determined from a combination of single MS and the tandem (MS/MS) spectra. Determination of the unique isomeric motif for each component is made possible via the following features of library design: (1) pan of the scafforld moiety, "transferable group" (the nitrogen atom from the oxime group) is transferred to the: substituent during fragmentation in the tandem experiment, (2) transferable groups on the scaffold differ from each other by either isotopic labels or fragmentation energies, and (3) mass-redundant substituents are isotopically labeled to create at least a 2 mass unit difference between them. The components of thr resulting library thus become labeled with different mass- and energy tags, which allows for precise regiochemical assignment of the functional group positions on the scaffold and substituents by mass spectrometry. The approach has been used to create and analyze a mixture of 27 isomeric compounds, each containing three boronic acid groups. The combination of the MS and MS/MS spectra of the tagged mixture has yielded a unique and structurally definitive signature of each component. Applications of the regiochemical tagging techniques to rapid synthesis and screening of combinatorial mixtures are discussed.

  DOI：

  10.1021/ja993844v

文献信息

• Quasielastic neutron scattering of –NH3 and –BH3 rotational dynamics in orthorhombic ammonia borane
  作者：Nancy J. Hess、Michael R. Hartman、Craig M. Brown、Eugene Mamontov、Abhijeet Karkamkar、David J. Heldebrant、Luc L. Daemen、Tom Autrey

  DOI：10.1016/j.cplett.2008.04.130

  日期：2008.6

  Energy barriers for rotation of -NH3 and -BH3 in the orthorhombic phase of ammonia borane, NH3BH3, were determined using quasielastic neutron scattering (QENS). QENS confirms the 3-site jump model of rotational diffusion and yields barrier heights of 23.6 +/- 1.0 kJ/mol and 14.8 +/- 0.4 kJ/mol for the borane and amine groups, respectively, which are comparable to barrier heights determined by recent H-2 and N-15 NMR studies suggesting no significant isotope effect on rotational motion in the orthorhombic phase of ammonia borane. Published by Elsevier B.V.
• Structure and vibrational dynamics of isotopically labeled lithium borohydride using neutron diffraction and spectroscopy
  作者：Michael R. Hartman、John J. Rush、Terrence J. Udovic、Robert C. Bowman、Son-Jong Hwang

  DOI：10.1016/j.jssc.2007.01.031

  日期：2007.4

  The crystalline structure of a Li-7 and B-11 labeled lithium borohydride has been investigated using neutron powder diffraction at 3.5, 360, and 400 K. The B-H bond lengths and H-B-H angles for the [BH4](-) tetrahedra indicated that the tetrahedra maintained a nearly ideal configuration throughout the temperature range investigated. The atomic displacement parameters at 360 K suggest that the [BH4](-) tetrahedra become increasingly disordered as a result of large amplitude librational and reorientational motions as the orthorhombic to hexagonal phase transition (T = 384 K) is approached. In the high-temperature hexagonal phase, the [BH4](-) tetrahedra displayed extreme disorder about the trigonal axis along which they are aligned. Neutron vibrational spectroscopy data were collected at 5 K over an energy range of 10-170meV, and were found to be in good agreement with prior Raman and low-resolution neutron spectroscopy studies. (C) 2007 Elsevier Inc. All rights reserved.