1-(2-hydroxyethyl)piperazinium ion

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 二嗪烷类
• 英文名称: 1-(2-hydroxyethyl)piperazinium ion
• 英文别名: 2-Piperazin-4-ium-1-ylethanol
• 化学式: C₆H₁₄N₂O*H
• 分子量: 131.198
• InChiKey: WFCSWCVEJLETKA-UHFFFAOYSA-O

计算性质

• 辛醇/水分配系数(LogP)：
  -1.1
• 重原子数：
  9
• 可旋转键数：
  2
• 环数：
  1.0
• sp3杂化的碳原子比例：
  1.0
• 拓扑面积：
  36.7
• 氢给体数：
  3
• 氢受体数：
  2

反应信息

• 作为反应物：
  描述：

  1-(2-hydroxyethyl)piperazinium ion 、 Ethoxy-(4-nitrophenoxy)methanethione 在 potassium chloride 作用下， 以 水 为溶剂， 生成
  参考文献：
  名称：

  Kinetics and Mechanism of the Aminolysis of Phenyl and 4-Nitrophenyl Ethyl Thionocarbonates

  摘要：

  The reactions of the title substrates (PTOC and NPTOC, respectively) with secondary alicyclic amines are subjected to a kinetic study in aqueous solution at 25.0 degrees C, ionic strength 0.2 M (KCI). Under amine excess, pseudo-first-order rate coefficients (k(obsd)) are found throughout. The order in amine is one for the reactions of piperidine but is of intermediate order between 1 and 2 for the reactions of the other amines. The kinetic results can be accommodated by a reaction scheme with two hypothetical tetrahedral intermediates: a zwitterionic (T-+/-) and an anionic (T-) one, whereby amine catalysis (deprotonation of T-+/- to give T-) is kinetically important. Both the pK(a) of T-+/- and the rate coefficient for proton transfer (k(3) ca. 10(10) s(-1) M(-1)) are estimated. The values of the other rate microcoefficients of the scheme are found by a nonlinear least-squares fitting, and these values are compared with those exhibited in the aminolysis of phenyl thionoacetate (PTOA), and S-phenyl and S-(4-nitrophenyl) O-ethyl dithiocarbonates (PDTC and NPDTC, respectively). The Bronsted type plots for amine basicity have slopes beta(N) ca, 0.2 for rate-determining amine attack (k(1)) and beta(N) ca. 0.8 for amine expulsion from T-+/- (k(-1)), in accord with the beta(N) values found in similar aminolyses. The general base catalysis by amine found in the aminolysis of NPTOC, in contrast with the lack of such catalysis in the aminolysis of 4-nitrophenyl methyl carbonate, is explained by a smaller rate coefficient for expulsion of 4-nitrophenoxide (k(2)) from T-+/- (which competes with amine deprotonation of T-+/-) relative to the same expulsion from the analogous oxy intermediate.

  DOI：

  10.1021/jo951726u
• 作为产物：
  描述：

  在 potassium chloride 作用下， 以 水 为溶剂， 生成 1-(2-hydroxyethyl)piperazinium ion 、 Ethoxy-(4-nitrophenoxy)methanethione
  参考文献：
  名称：

  Kinetics and Mechanism of the Aminolysis of Phenyl and 4-Nitrophenyl Ethyl Thionocarbonates

  摘要：

  The reactions of the title substrates (PTOC and NPTOC, respectively) with secondary alicyclic amines are subjected to a kinetic study in aqueous solution at 25.0 degrees C, ionic strength 0.2 M (KCI). Under amine excess, pseudo-first-order rate coefficients (k(obsd)) are found throughout. The order in amine is one for the reactions of piperidine but is of intermediate order between 1 and 2 for the reactions of the other amines. The kinetic results can be accommodated by a reaction scheme with two hypothetical tetrahedral intermediates: a zwitterionic (T-+/-) and an anionic (T-) one, whereby amine catalysis (deprotonation of T-+/- to give T-) is kinetically important. Both the pK(a) of T-+/- and the rate coefficient for proton transfer (k(3) ca. 10(10) s(-1) M(-1)) are estimated. The values of the other rate microcoefficients of the scheme are found by a nonlinear least-squares fitting, and these values are compared with those exhibited in the aminolysis of phenyl thionoacetate (PTOA), and S-phenyl and S-(4-nitrophenyl) O-ethyl dithiocarbonates (PDTC and NPDTC, respectively). The Bronsted type plots for amine basicity have slopes beta(N) ca, 0.2 for rate-determining amine attack (k(1)) and beta(N) ca. 0.8 for amine expulsion from T-+/- (k(-1)), in accord with the beta(N) values found in similar aminolyses. The general base catalysis by amine found in the aminolysis of NPTOC, in contrast with the lack of such catalysis in the aminolysis of 4-nitrophenyl methyl carbonate, is explained by a smaller rate coefficient for expulsion of 4-nitrophenoxide (k(2)) from T-+/- (which competes with amine deprotonation of T-+/-) relative to the same expulsion from the analogous oxy intermediate.

  DOI：

  10.1021/jo951726u

文献信息

• Kinetics and mechanism of the aminolysis of 4-nitrophenyl and 2,4-dinitrophenyl 4-methylphenyl carbonates in aqueous ethanol
  作者：Enrique A. Castro、Monica Andujar、Paola Campodonico、Jos� G. Santos

  DOI：10.1002/kin.10046

  日期：——

  in accordance with a stepwise mechanism, through a zwitterionic tetrahedral intermediate (T±), and a change in the rate-determining step, from formation to breakdown of T± as the amine pKa decreases. For the aminolysis of MPDNPC, a slightly curved Bronsted-type plot for kN is obtained, with β1 = 0.1 (low pKa) and β2 = 0.55 (high pKa). This is consistent with a concerted mechanism. © 2002 Wiley Periodicals

  对 4-甲基苯基 4-硝基苯基碳酸酯 (MPNPC) 和 4-甲基苯基 2,4-二硝基苯基碳酸酯 (MPDNPC) 与一系列脂环族仲胺的反应在 44 wt% 乙醇-水中进行动力学研究，温度为 25.0° C、离子强度 0.2 M (KCl)。在胺过量的情况下，获得了伪一级速率系数 (kobs)。kobs 对 [amine] 的图是线性的，以 kN 为斜率。对于 MPNPC 的氨解，获得了 kN 的双相布朗斯台德型图，斜率 β1 = 0.2（高 pKa）和 β2 = 0.9（低 pKa）。这与通过两性离子四面体中间体 (T±) 的逐步机制以及决速步骤中的变化一致，即随着胺 pKa 的降低，从 T± 的形成到分解。对于 MPDNPC 的氨解，获得了 kN 的略微弯曲的布朗斯台德图，β1 = 0.1（低 pKa）和 β2 = 0.55（高 pKa）。这与协调机制一致。© 2002 Wiley Periodicals
• Structure-reactivity correlations in the aminolysis of aryl chloroformates
  作者：Enrique A. Castro、Mar�a G. Ruiz、Jos� G. Santos

  DOI：10.1002/kin.1022

  日期：——

  pH 6.2–7.3. The Bronsted-type plots for the kN values for the aminolysis of both chloroformates are linear, with slopes ca. 0.3, which is consistent with rate-determining formation of a zwitterionic tetrahedral intermediate (T±). With the pKa and log kN data for the present reactions, together with those for the same aminolysis of phenyl and 4-nitrophenyl chloroformates, two dual parametric equations

  在 25.0°C、离子强度 0.2 M (KCl) 的水中，对一系列仲脂环胺与 4-甲基苯基和 4-甲氧基苯基氯甲酸酯的反应进行了动力学研究。在胺过量的情况下，发现所有反应的伪一级速率系数 (kobs)。kobs 与 [NH]（NH 是游离胺）的曲线是线性的，斜率 (kN) 与 pH 无关，除了 1-(2-羟乙基)哌嗪与两种底物在 pH 6.2-7.3 的反应。两种氯甲酸酯的氨解的 kN 值的布朗斯台德型图是线性的，斜率约为。0.3，这与两性离子四面体中间体 (T±) 的速率决定形成一致。使用本反应的 pKa 和 log kN 数据，以及苯基和 4-硝基苯基氯甲酸酯的相同氨解的数据，对于 log kN 作为亲核试剂的 pKa、“非离去”组的 Hammett sigma 和“非离去”组的 pKa 的函数，找到了两个双参数方程，系数 βN = 0.3、ρnlg = 0.7 和 βnlg = -
• Kinetics and Mechanism of the Aminolysis of Methyl 4-Nitrophenyl, Methyl 2,4-Dinitrophenyl, and Phenyl 2,4-Dinitrophenyl Carbonates
  作者：Enrique A. Castro、Margarita Aliaga、Paola Campodónico、José G. Santos

  DOI：10.1021/jo026390k

  日期：2002.12.1

  The reactions of methyl 4-nitrophenyl carbonate (MNPC) with a series of secondary alicyclic amines (SAA) and quinuclidines (QUIN), methyl 2,4-dinitrophenyl carbonate (MDNPC) with QUIN and 1-(2-hydroxyethyl)piperazinium ion (HPA), and phenyl 2,4-dinitrophenyl carbonate (PDNPC) with SAA are subjected to a kinetic investigation in aqueous solution, at 25.0 degrees C and an ionic strength of 0.2 M. By

  甲基4-硝基苯基碳酸酯（MNPC）与一系列仲脂环族胺（SAA）和喹啉核苷（QUIN），甲基2,4-二硝基苯基碳酸酯（MDNPC）与QUIN和1-（2-羟乙基）哌嗪离子的反应（ HPA）和带有SAA的碳酸2,4-二硝基苯基苯基酯（PDNPC）在水溶液中于25.0摄氏度和0.2 M的离子强度下进行动力学研究。通过分光光度法跟踪核试剂的释放（330-400 nm）在胺过量的情况下，获得伪一阶速率系数（k（obsd））。在恒定pH下k（obsd）与[胺]的图呈线性关系，斜率（k（N））与pH无关。SAA与MNPC反应的布朗斯台德图（log k（N）vs胺pK（a））是双相的，斜率beta（1）= 0.3（高pK（a）区域）和beta（2）= 1 。0（低pK（a）区域）和曲率中心位于pK（a）（0）= 9.3。该图与通过两性离子四面体中间体（T（+/-））的逐步机理以及SAA碱度决定速率的步骤的变
• Kinetics and Mechanism of the Aminolysis of 4-Methylphenyl and 4-Chlorophenyl 2,4-Dinitrophenyl Carbonates in Aqueous Ethanol
  作者：Enrique A. Castro、Paola Campodonico、Alejandra Toro、José G. Santos

  DOI：10.1021/jo034385q

  日期：2003.7.1

  concerted, although it is also possible that both mechanisms (stepwise and concerted) operate simultaneously. By comparison of the reactions under investigation between them and with similar aminolyses, the following conclusions can be drawn: (i) ClPDNPC is more reactive than MPDNPC toward the two amine series. (ii) The change of water to aqueous ethanol destabilizes a zwitterionic tetrahedral intermediate

  苯胺与4-甲基苯基和4-氯苯基2,4-二硝基苯基碳酸酯（分别为MPDNPC和ClPDNPC）和后者的底物与仲脂环族（SA）胺的反应在44 wt％乙醇-水溶液中进行动力学研究，在25.0摄氏度，离子强度为0.2 M（KCl）。通过分光光度法（360 nm）释放2,4-二硝基苯氧根阴离子来研究反应。在胺过量的情况下，发现伪一阶速率系数（k（obsd））。k（obsd）对[胺]的图是线性的且与pH无关，斜率为k（N）。苯胺与MPDNPC和ClPDNPC的反应的布朗斯台德图（log k（N）vs pK（a）的铝离子）是线性的，斜率分别为β= 0.68和0.66，对于苯胺的反应，斜率为β= 0.44。 SA胺与ClPDNPC。后一种反应的斜率大小表明其机理是一致的。苯胺反应的斜率值在逐步机理和协同机理之间的边界处。logk（N）对非离去基团（beta（nlg））的碱性的敏感性为ca。-0.7对于苯胺
• Kinetics and mechanism of the aminolysis of 4-nitrophenyl dithioacetate
  作者：Enrique A. Castro、Fernando Ibanez、Jose G. Santos、Carmen Ureta

  DOI：10.1021/jo00052a010

  日期：1992.12

  The reaction of the title substrate with a series of secondary alicylic amines has been the subject of a kinetic study in aqueous solution, 25-degrees-C, ionic strength 0.2 M (KCl). With the amine in excess, pseudo-first-order rate constants (k(obsd)) are observed. The order in amine varies from 1 to 2 depending on the basicity of the amine and the reaction conditions. A reaction scheme is deduced on the basis of the existence of zwitterionic (T+/-) and anionic (T-) tetrahedral intermediates. Proton transfer from T+/- to an amine or base (to yield T-) seems to compete with 4-nitrothiophenoxide (NPS-) expulsion from T+/-. The pK(a) of T+/- and all the rate microconstants of the scheme are estimated. The rates of expulsion of NPS- and amine from T+/- are smaller than those from analogous T+/- formed in the aminolyses of O-ethyl S-(4-nitrophenyl) dithiocarbonate and 4-nitrophenyl thiolacetate. It is claimed that substitution of Me by RO (R = alkyl) or S- by O- in T+/- destablizes this intermediate.