methyl 2-((2,2,6,6-tetramethylpiperidin-1-yl)oxy)acetate | 917871-76-2

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 哌啶类
• 英文名称: methyl 2-((2,2,6,6-tetramethylpiperidin-1-yl)oxy)acetate
• 英文别名: Methyl [(2,2,6,6-tetramethylpiperidin-1-yl)oxy]acetate；methyl 2-(2,2,6,6-tetramethylpiperidin-1-yl)oxyacetate
• CAS: 917871-76-2
• 化学式: C₁₂H₂₃NO₃
• 分子量: 229.32
• InChiKey: SZWZJTWEXMLNCB-UHFFFAOYSA-N

物化性质

• 沸点：
  265.0±42.0 °C(Predicted)
• 密度：
  1.01±0.1 g/cm3(Predicted)

计算性质

• 辛醇/水分配系数(LogP)：
  2.3
• 重原子数：
  16
• 可旋转键数：
  4
• 环数：
  1.0
• sp3杂化的碳原子比例：
  0.92
• 拓扑面积：
  38.8
• 氢给体数：
  0
• 氢受体数：
  4

反应信息

• 作为反应物：
  描述：

  methyl 2-((2,2,6,6-tetramethylpiperidin-1-yl)oxy)acetate 在 potassium hydroxide 作用下， 以 四氢呋喃 为溶剂， 反应 24.0h， 生成 2-(2,2,6,6-tetramethylpiperidin-1-yloxy)acetic acid
  参考文献：
  名称：

  氢键约束肽中丝氨酸和苏氨酸残基的自由基反应动力学。

  摘要：

  自由基引发的肽测序（FRIPS）质谱从在目标肽中引入高度选择性的低能解离途径中获得了优势。通过碰撞活化和随后共价连接的自由基前体的离解在肽N端形成的乙酰基，从肽的不同位点提取氢原子，通过主链裂解以及侧链丢失产生序列信息。在丝氨酸和苏氨酸残基观察到独特的自由基引发的离解途径导致相邻的N-终端C的裂解α -C或N-C α键而不是典型的C α其他氨基酸可观察到–C键断裂。通过FRIPS对ARAAAXAAAA形式的模型肽进行了研究，其中X是目标氨基酸。结合密度泛函理论（DFT）计算，实验表明在丝氨酸或苏氨酸上的氢键对观察到的自由基化学有强烈影响。与主链羰基氧对齐到的侧链羟基基团的氢键键合的单占据π轨道上的β碳和N-C α键，导致N-C的低势垒β裂解α键。用N-末端羰基相互作用有利于氢原子转移过程，以产生稳定的c型和z •离子，而C末端相互作用导致的C有效裂解α-C键通过迅速失去异氰酸而键合。作为C离解α

  DOI：

  10.1021/jp501367w
• 作为产物：
  描述：

  2,2,6,6-四甲基哌啶氧化物 、 methoxycarbonyl-methyl 以 乙腈 为溶剂， 生成 methyl 2-((2,2,6,6-tetramethylpiperidin-1-yl)oxy)acetate
  参考文献：
  名称：

  Entropy Control of the Cross-Reaction between Carbon-Centered and Nitroxide Radicals

  摘要：

  Absolute rate constants for the cross-coupling reaction of several carbon-centered radicals with various nitroxides and their temperature dependence have been determined in liquids by kinetic absorption spectroscopy. The rate constants range from <2 x 10(5) M-1 s(-1) to 2.3 x 10(9) M-1 s(-1) and depend strongly on the structure of the nitroxide and the carbon-centered radical. Grossly, they decrease with increasing rate constant of the cleavage of the corresponding alkoxyamine. In many cases, the temperature dependence shows a non-Arrhenius behavior. A model assuming a short-lived intermediate that is hindered to form the coupling product by an unfavorable activation entropy leads to a satisfactory analytic description. However, the behavior is more likely due to a barrierless single-step reaction with a low exothermicity where the free energy of activation is dominated by a large negative entropy term.

  DOI：

  10.1021/ja0036460

文献信息

• Photochemical α-carboxyalkylation of tryptophols and tryptamines <i>via</i> C–H functionalization
  作者：Zhiqiang Pan、Yuchang Liu、Fengchi Hu、Qinglong Liu、Wenbin Shang、Chengfeng Xia

  DOI：10.1039/d0cc00847h

  日期：——

  strategy activated the C-Br bonds of α-bromo-alkylcarboxylic esters to provide carbon-centered radicals under the catalysis of Ir(iii) photocatalyst and coupled with indole derivatives. This methodology displayed wide functional group tolerance and excellent regioselectivity, and was applied to the late-stage functionalization and preparation of indole-containing hybrids.

  已经开发了在可见光照射下通过CH键的官能化使色酚和色胺的α-羧烷基化的方法。该光化学策略在Ir（iii）光催化剂的催化下并与吲哚衍生物偶联，活化了α-溴代烷基羧酸酯的C-Br键以提供以碳为中心的自由基。该方法显示出宽泛的官能团耐受性和优异的区域选择性，并应用于后期功能化和含吲哚杂种的制备。
• Triphenylphosphine oxide promoting visible-light-driven C–C coupling <i>via</i> desulfurization
  作者：Shea Stewart、Robert Maloney、Yugang Sun

  DOI：10.1039/d3cc00001j

  日期：——

  Triphenylphosphine oxide (TPPO) and triphenylphosphine (TPP) can form a complex in solution, promoting visible light absorption to trigger electron transfer within the complex and generate radicals. Subsequent radical reactions with thiols enable desulfurization to produce carbon radicals that react with aryl alkenes to yield new C–C bonds. Since ambient oxygen can easily oxidize TPP to TPPO, the reported

  三苯基氧化膦 (TPPO) 和三苯基膦 (TPP) 可以在溶液中形成络合物，促进可见光吸收以触发络合物内的电子转移并产生自由基。随后与硫醇的自由基反应使脱硫产生碳自由基，碳自由基与芳基烯烃反应产生新的 C-C 键。由于环境氧气很容易将 TPP 氧化成 TPPO，因此所报道的方法不需要明确添加光催化剂。这项工作突出了在有机合成中使用 TPPO 作为催化光氧化还原介质的前景。
• Photoredox‐Catalyzed Carbon Radical Generation from α‐Keto‐<i>N</i>,<i>O</i>‐acetals: Synthesis of Functionalized Azepino[1,2‐<i>a</i>]indoles and Azepino[1,2‐<i>a</i>]furo[3,2‐<i>b</i>]indoles
  作者：Paul Seefeldt、Alexander Villinger、Malte Brasholz

  DOI：10.1002/adsc.202300967

  日期：2024.1.9

  catalyst-free reaction showed any conversion of acetate 2 a (entries 14 and 15). As depicted in Scheme 2a, the PPTH-photocatalyzed radical addition of several tetrahydroazepino[1,2-a]indole acetates 2 a–c, all made from the parent functionalized cyclohepta[b]indoles 1 by catalytic photooxygenation, and silyl enol ethers 5 a–c under 380 nm LED irradiation, gave β-amino ketone products 7 aa–7 ca in moderate

  α-羰基自由基是合成官能化羰基化合物中非常有用的反应中间体。1通过光氧化还原催化 SET 还原 α-卤代羰基前体来生成它们是一种温和且方便的方法，可以补充基于卤素原子抽象反应的更传统方案（方案 1a，左）。在第一个例子中，福住等人。1990 年和斯蒂芬森等人。2009年报道了α-溴酮2和α-卤代羧酸盐的光氧化还原催化还原脱卤。3随后的发展包括引入新的光催化系统，4 α-氟酮和羧酸盐的显着活化，5以及在大量新的自由基加成和环化中利用光催化产生的亲电子 α-羰基自由基，从而产生多种无环化合物。和（杂）环分子结构。6由于 α-含氧羰基化合物的负还原电位更大，因此通过 SET 还原生成 α-羰基自由基相对更具挑战性。然而，α-羟基羰基化合物非常丰富，使得这种还原性 CO 裂解反应极具吸引力（方案 1a，右）。 方案一 在图查看器中打开微软幻灯片软件 a)通过光氧化还原催化对α-卤代和α-氧化羰基化
• Entropy Control of the Cross-Reaction between Carbon-Centered and Nitroxide Radicals
  作者：Jens Sobek、Rainer Martschke、Hanns Fischer

  DOI：10.1021/ja0036460

  日期：2001.3.1

  Absolute rate constants for the cross-coupling reaction of several carbon-centered radicals with various nitroxides and their temperature dependence have been determined in liquids by kinetic absorption spectroscopy. The rate constants range from <2 x 10(5) M-1 s(-1) to 2.3 x 10(9) M-1 s(-1) and depend strongly on the structure of the nitroxide and the carbon-centered radical. Grossly, they decrease with increasing rate constant of the cleavage of the corresponding alkoxyamine. In many cases, the temperature dependence shows a non-Arrhenius behavior. A model assuming a short-lived intermediate that is hindered to form the coupling product by an unfavorable activation entropy leads to a satisfactory analytic description. However, the behavior is more likely due to a barrierless single-step reaction with a low exothermicity where the free energy of activation is dominated by a large negative entropy term.
• Hydrogen Bonding Constrains Free Radical Reaction Dynamics at Serine and Threonine Residues in Peptides
  作者：Daniel A. Thomas、Chang Ho Sohn、Jinshan Gao、J. L. Beauchamp

  DOI：10.1021/jp501367w

  日期：2014.9.18

  or N–Cα bond rather than the typical Cα–C bond cleavage observed with other amino acids. These reactions were investigated by FRIPS of model peptides of the form AARAAAXAA, where X is the amino acid of interest. In combination with density functional theory (DFT) calculations, the experiments indicate the strong influence of hydrogen bonding at serine or threonine on the observed free radical chemistry

  自由基引发的肽测序（FRIPS）质谱从在目标肽中引入高度选择性的低能解离途径中获得了优势。通过碰撞活化和随后共价连接的自由基前体的离解在肽N端形成的乙酰基，从肽的不同位点提取氢原子，通过主链裂解以及侧链丢失产生序列信息。在丝氨酸和苏氨酸残基观察到独特的自由基引发的离解途径导致相邻的N-终端C的裂解α -C或N-C α键而不是典型的C α其他氨基酸可观察到–C键断裂。通过FRIPS对ARAAAXAAAA形式的模型肽进行了研究，其中X是目标氨基酸。结合密度泛函理论（DFT）计算，实验表明在丝氨酸或苏氨酸上的氢键对观察到的自由基化学有强烈影响。与主链羰基氧对齐到的侧链羟基基团的氢键键合的单占据π轨道上的β碳和N-C α键，导致N-C的低势垒β裂解α键。用N-末端羰基相互作用有利于氢原子转移过程，以产生稳定的c型和z •离子，而C末端相互作用导致的C有效裂解α-C键通过迅速失去异氰酸而键合。作为C离解α