4-methyl-1-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,4-dihydropyridine | 1345455-99-3

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡啶及其衍生物
• 英文名称: 4-methyl-1-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,4-dihydropyridine
• 英文别名: 4-methyl-1-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-4H-pyridine
• CAS: 1345455-99-3
• 化学式: C₁₂H₂₀BNO₂
• 分子量: 221.107
• InChiKey: FLSOCNIJZUITBU-UHFFFAOYSA-N

物化性质

• 沸点：
  238.8±50.0 °C(Predicted)
• 密度：
  1.01±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  2.55
• 重原子数：
  16
• 可旋转键数：
  1
• 环数：
  2.0
• sp3杂化的碳原子比例：
  0.67
• 拓扑面积：
  21.7
• 氢给体数：
  0
• 氢受体数：
  3

反应信息

• 作为产物：
  描述：

  4-甲基吡啶 、 频那醇硼烷 在 manganese(II) bis(trimethylsilyl)amide 作用下， 以 氘代苯 为溶剂， 反应 72.0h， 生成 4-methyl-1-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,4-dihydropyridine 、 4-methyl-1-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2-dihydropyridine
  参考文献：
  名称：

  范围广泛的锰催化硼氢化反应

  摘要：

  容易获得的氧化物质的还原转化是合成操作和化学价值化的核心。催化加氢官能化的应用受益于液体还原剂的使用和操作简便的设置。金属催化的硼氢化反应为稳定的 C=X 亲电试剂的还原增值提供了一个高产的平台。在这里，我们报告了在非常温和的条件下，使用廉价的预催化剂 Mn(hmds) 2可以特别轻松、广泛地还原各种功能，包括羰基化合物、羧酸盐、吡啶、碳二亚胺和碳酸盐。该反应可以成功地应用于解聚。

  DOI：

  10.1002/anie.202103550

文献信息

• Alkoxide‐Promoted Selective Hydroboration of<i>N</i>‐Heteroarenes: Pivotal Roles of in situ Generated BH₃in the Dearomatization Process
  作者：Eunchan Jeong、Joon Heo、Sehoon Park、Sukbok Chang

  DOI：10.1002/chem.201901214

  日期：2019.5.2

  While numerous organo(metallic)catalyst systems were documented for dearomative hydroboration of N‐aromatics, alkoxide base catalysts have not been disclosed thus far. Described herein is the first example of alkoxide‐catalyzed hydroboration of N‐heteroaromatics including pyridines, providing a broad range of reduced N‐heterocycles with high efficiency and selectivity. Mechanistic studies revealed

  尽管有许多有机（金属）催化剂体系被记录用于N-芳烃的脱芳烃硼氢化反应，但迄今为止尚未公开醇盐基催化剂。本文介绍的是烷氧基催化的N-杂芳族化合物（包括吡啶）的硼氢化反应的第一个实例，可提供范围广泛的还原N-杂环，具有高效率和选择性。机理研究揭示了前所未有的违反直觉的脱芳香化途径，其中1）吡啶-BH 3加合物受到烷氧基硼氢化物的氢化物攻击，2）原位生成的BH 3充当催化促进剂，3）1,4-二氢吡啶基硼氢化物处于主要的休息状态。
• Regioselective 1,4-hydroboration of pyridines catalyzed by an acid-initiated boronium cation
  作者：Evan N. Keyzer、Sky S. Kang、Schirin Hanf、Dominic S. Wright

  DOI：10.1039/c7cc04988a

  日期：——

  The reaction of the commercially available ammonium salt NH4BPh4 with a pyridine-activated pinacolborane species generates a boronium cation that facilitates the 1,4-selective hydroboration of pyridines in polar solvents. This catalytic reaction is amenable to a host of reactive functional groups and provides access to sterically bulky hydroboration products, previously inaccessible by metal-free routes

  市售铵盐NH 4 BPh 4与吡啶活化的频哪醇硼烷物质的反应生成硼阳离子，该硼阳离子促进吡啶在极性溶剂中的1,4-选择性氢硼化。该催化反应适合于许多反应性官能团，并提供了空间庞大的硼氢化产物的通道，该通道以前是无金属途径无法达到的。此外，该反应的区域选择性可以通过降低反应溶剂的极性来改变，从而导致更大比例的1，2-氢硼化产物。
• A Manganese Nanosheet: New Cluster Topology and Catalysis
  作者：Uttam Chakraborty、Efrain Reyes-Rodriguez、Serhiy Demeshko、Franc Meyer、Axel Jacobi von Wangelin

  DOI：10.1002/anie.201800079

  日期：2018.4.23

  and the surface characteristics of larger metal particles are well understood, preparations of molecular metallic nanoclusters remain a great challenge. Discrete planar metal clusters constitute nanoscale snapshots of cluster growth but are especially rare owing to the strong preference for three‐dimensional structures and rapid aggregation or decomposition. A simple ligand‐exchange procedure has led

  虽然单金属配合物的配位化学和较大金属颗粒的表面特征已被充分了解，但分子金属纳米团簇的制备仍然是一个巨大的挑战。离散的平面金属簇构成簇生长的纳米级快照，但由于对三维结构和快速聚集或分解的强烈偏好而特别罕见。一个简单的配体交换过程导致了一种新型杂配Mn 6纳米团簇的形成，该纳米团簇以前所未有的平椅拓扑结晶，并表现出独特的磁性和催化性能。磁化率研究记录了锰离子之间强烈的电子通讯。Mn 6分子簇的还原活化能够实现烯烃、炔烃和亚胺的催化氢化。
• Magnesium-Catalyzed Hydroboration of Pyridines
  作者：Merle Arrowsmith、Michael S. Hill、Terrance Hadlington、Gabriele Kociok-Köhn、Catherine Weetman

  DOI：10.1021/om2008138

  日期：2011.11.14

  Reaction of catalytic quantities of a beta-diketiminato n-butylmagnesium complex with pinacol-borane in the presence of pyridine derivatives provides facile access to borylated dihydropyridines. The reaction is applicable to a wide range of monocyclic and fused-ring pyridine derivatives and catalytic turnover is proposed to occur through a well-defined sequence of Mg-H/pyridine dearomatization and Mg-N/B-H sigma bond metathesis steps.
• Multinuclear Magnesium Hydride Clusters: Selective Reduction and Catalytic Hydroboration of Pyridines
  作者：Julia Intemann、Martin Lutz、Sjoerd Harder

  DOI：10.1021/om500469h

  日期：2014.10.27

  Multinuclear magnesium hydride complexes react with pyridine, forming 1,2- and 1,4-dihydropyridide (DHP) complexes. Reaction of PARA(3)Mg(8)H(10) with pyridine initially formed 1,2-DHP and 1,4-DHP product mixtures which converted at 60 degrees C into PARA-[Mg(1,4-DHP)]2.(pyridine)2 (PARA = [(2,6-iPr2C6H3)NC(Me)C(H)C(Me)N]2-(p-C6H4)). Reaction of [NN-(MgH)(2)](2) with pyridine gave exclusive formation of the 1,2-DHP product NN-[Mg(1,2-DHP)](2).(pyridine)2 (NN = [(2,6-iPr(2)C(6)H(3))NC(Me)CHC(Me)N-](2)). Both products were characterized by crystal structure determinations. The unusual preference for 1,2-addition is likely caused by secondary intramolecular interactions based on mutual communication between the metal coordination geometries: an extended network of CH...C p-interactions and p-stacking interactions is found. Whereas PARA3Mg(8)H(10) is hardly active in magnesium-catalyzed hydroboration of pyridines with pinacolborane, [NN-(MgH)(2)](2) shows efficient coupling. However, the regioselectivity of the stoichiometric reaction is not translated to the catalytic regime. This result is taken as an indication for a potential alternative mechanism in which magnesium hydride intermediates do not play a role but the hydride is transferred from an intermediate borate complex.