{"title":"核磁共振作为双相pKa测量技术","authors":"Andre Leesment, Sigrid Selberg, I. Leito","doi":"10.25135/jcm.79.2211.2639","DOIUrl":null,"url":null,"abstract":": NMR is a powerful technique with a wide range of applications, including measurements of acid dissociation constants (p K a values). One such example where NMR is particularly valuable is the measurement of biphasic octanol-water p K a (p K aow ) values. Acid-base properties in biphasic systems (extraction systems, lipid bilayers, phase-transfer catalysis systems) are commonly estimated from single-phase (typically aqueous) p K a values. However, acid-base properties in biphasic systems are more complex than in systems consisting of one phase and the single-phase p K a value does not adequately describe the situation. Biphasic p K a values (such as octanol:water biphasic p K a values, p K a ow ) have been introduced to provide a more realistic description of behaviour acids in biphasic systems. 1 H and 13 C NMR have been used extensively for p K a ow measurements and their advantages and disadvantages have been discussed in detail. However, the suitability of 31 P NMR has not yet been assessed in depth and 19 F NMR has until now not been used for p K a ow measurements at all. In this study, we measure p K a ow values with 1 H, 13 C, 19 F and 31 P NMR and provide a detailed comparison of NMR with these four nuclei in terms of p K aow measurement.","PeriodicalId":15343,"journal":{"name":"Journal of Chemical Metrology","volume":null,"pages":null},"PeriodicalIF":1.8000,"publicationDate":"2022-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"NMR as biphasic pKa measurement technique\",\"authors\":\"Andre Leesment, Sigrid Selberg, I. Leito\",\"doi\":\"10.25135/jcm.79.2211.2639\",\"DOIUrl\":null,\"url\":null,\"abstract\":\": NMR is a powerful technique with a wide range of applications, including measurements of acid dissociation constants (p K a values). One such example where NMR is particularly valuable is the measurement of biphasic octanol-water p K a (p K aow ) values. Acid-base properties in biphasic systems (extraction systems, lipid bilayers, phase-transfer catalysis systems) are commonly estimated from single-phase (typically aqueous) p K a values. However, acid-base properties in biphasic systems are more complex than in systems consisting of one phase and the single-phase p K a value does not adequately describe the situation. Biphasic p K a values (such as octanol:water biphasic p K a values, p K a ow ) have been introduced to provide a more realistic description of behaviour acids in biphasic systems. 1 H and 13 C NMR have been used extensively for p K a ow measurements and their advantages and disadvantages have been discussed in detail. However, the suitability of 31 P NMR has not yet been assessed in depth and 19 F NMR has until now not been used for p K a ow measurements at all. In this study, we measure p K a ow values with 1 H, 13 C, 19 F and 31 P NMR and provide a detailed comparison of NMR with these four nuclei in terms of p K aow measurement.\",\"PeriodicalId\":15343,\"journal\":{\"name\":\"Journal of Chemical Metrology\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.8000,\"publicationDate\":\"2022-12-31\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Chemical Metrology\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.25135/jcm.79.2211.2639\",\"RegionNum\":0,\"RegionCategory\":null,\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"CHEMISTRY, ANALYTICAL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Chemical Metrology","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.25135/jcm.79.2211.2639","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"CHEMISTRY, ANALYTICAL","Score":null,"Total":0}
引用次数: 0
摘要
:核磁共振是一种强大的技术,具有广泛的应用,包括测量酸离解常数(p K a值)。NMR特别有价值的一个这样的例子是测量双相辛醇-水p K a(p K aow)值。双相系统(萃取系统、脂质双层、相转移催化系统)中的酸碱性质通常由单相(通常为水性)p K a值估计。然而,双相系统中的酸碱性质比单相系统中的更复杂,单相p K a值不能充分描述这种情况。引入了双相p K a值(如辛醇:水双相p K a值,p K a ow),以提供对双相系统中行为酸的更现实的描述。1H和13C NMR已被广泛用于p K a ow测量,并详细讨论了它们的优缺点。然而,31P NMR的适用性尚未得到深入评估,19F NMR迄今为止根本没有用于P K a ow测量。在这项研究中,我们用1H、13C、19F和31P NMR测量了pKaow值,并根据pKaow测量提供了NMR与这四个核的详细比较。
: NMR is a powerful technique with a wide range of applications, including measurements of acid dissociation constants (p K a values). One such example where NMR is particularly valuable is the measurement of biphasic octanol-water p K a (p K aow ) values. Acid-base properties in biphasic systems (extraction systems, lipid bilayers, phase-transfer catalysis systems) are commonly estimated from single-phase (typically aqueous) p K a values. However, acid-base properties in biphasic systems are more complex than in systems consisting of one phase and the single-phase p K a value does not adequately describe the situation. Biphasic p K a values (such as octanol:water biphasic p K a values, p K a ow ) have been introduced to provide a more realistic description of behaviour acids in biphasic systems. 1 H and 13 C NMR have been used extensively for p K a ow measurements and their advantages and disadvantages have been discussed in detail. However, the suitability of 31 P NMR has not yet been assessed in depth and 19 F NMR has until now not been used for p K a ow measurements at all. In this study, we measure p K a ow values with 1 H, 13 C, 19 F and 31 P NMR and provide a detailed comparison of NMR with these four nuclei in terms of p K aow measurement.