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1、P1:Hello everyone,welcome to todays class-Organic Spectroscopic Analysis.In this Chapter,we are going to learn a new spectroscopy techniqueNMR.NMR is the abbreviation of nuclear magnetic resonance.The absorption of electromagnetic radiation of a specific frequency by an atomic nucleus that is placed
2、 in a strong magnetic field,used especially in the study of the structures of organic compounds.P1：大家好，欢迎学习今天的课程有机波谱分析。在本章中，我们将学习一种新的波谱技术-核磁共振。NMR 是核磁共振的缩写。它的定义是被置于强磁场中的原子核吸收特定频率的电磁辐射，特别是用于研究有机化合物的结构。P3:Nuclear magnetic resonance was first described and measured in molecular beams by Isidor Rabi in
3、1938,and in 1944,Rabi was awarded the Nobel Prize in physics for this work.In 1946,Felix Bloch and Edward Mills Purcell expanded the technique for use on liquids and solids,for which they shared the Nobel Prize in Physics in 1952.P3：核磁共振最早是由 Isidor Rabi 在 1938 年用分子束描述和测量的，并且在 1944 年，Rabi 因这项工作而获得了诺贝
4、尔物理学奖。1946 年，费利克斯布洛赫（Felix Bloch）和爱德华米尔斯珀塞尔（Edward Mills Purcell）扩展了该技术在液体和固体上的应用，为此，他们于 1952 年获得了诺贝尔物理学奖。P4:Purcell had worked on the development of radar during World War II at the Massachusetts Institute of Technologys Radiation Laboratory.His work during that project on the production and detect
5、ion of radio frequency power and on the absorption of such RF power by matter laid the background for Rabis discovery of NMR.Different atomic nuclei within a molecule resonate at different(radio)frequencies for the same magnetic field strength.The observation of such magnetic resonance frequencies o
6、f the nuclei present in a molecule allows the trained user to discover essential,chemical and structural information about the molecule.P4：在第二次世界大战期间，普歇尔（Purchell）曾在麻省理工学院辐射实验室从事雷达的开发工作。他在该项目中有关产生和检测射频电波以及物质吸收此 RF 的工作为Rabi 发现 NMR 奠定了基础。对于相同的磁场强度，分子中不同的原子核会以不同的频率谐振。对分子中存在的原子核的这种磁共振频率的观察允许任何受过训练的用户发现关
7、于分子的化学和结构信息。P6:Richard R.Ernst won the Nobel Prize in Chemistry in 1991 for his contributions to the development of high resolution nuclear magnetic resonance spectroscopy“Which is(Fourier Transform NMR)”The polarized nuclear magnets of the nuclei begin to spin together,creating a radio frequency si
8、gnal that is observable.However,they ultimately lose alignment and simultaniously decay to the equilibrium state in the magnet of having a net polarization vector that aligns with the field.This time-dependent pattern can be converted into a frequency-dependent pattern of nuclear resonances using a
9、mathematical function known as a Fourier transformation,revealing the nuclear magnetic resonance spectrum.P6：理查德R恩斯特（Richard R.Ernst）因其对高分辨率核磁共振波谱学的发展做出的贡献而获得 1991 年诺贝尔化学奖。（傅里叶变换核磁共振）原子核的极化核磁体开始旋转，从而产生可观察到的射频信号。然而，它们最终失去有序排列，同时衰减到具有与磁场一致的净极化矢量的平衡状态。可以使用傅立叶变换的数学函数将这种与时间有关的模式转换为与核共振有关的频率相关模式，从而获得核磁共振谱
10、。P8:Kurt Wthrich receiving the Nobel Prize in Chemistry in 2002 for the structure determination of biomolecules like DNA and protein by NMR.P8：库尔特沃特里希（KurtWthrich）在 2002 年因采用 NMR 鉴定生物分子（如 DNA 和蛋白质）的结构而获得诺贝尔化学奖。P9:Paul Lauterbur and Peter Mansfield shared the 2003 Nobel Prize for their discoveries in
11、 the field of magnetic resonance imaging(MRI)P9：保罗 劳特伯（Paul Lauterbur）和彼得 曼斯菲尔德（Peter Mansfield）因在磁共振成像（MRI）领域的发现获得了 2003 年诺贝尔奖 P10:Magnetic resonance imaging using strong magnetic fields and radio waves,MRI collects and correlates signals caused by atoms(primarily H2O in human body)into images.Usin
12、g MRI technology,physicians are increasingly able to make diagnosis of serious pathology(e.g.,tumors)earlier,and earlier diagnosis often translates to a more favorable outcome for the patients.MRI tests offer relatively sharp pictures and allow physicians to see internal bodily structure with great
13、detail.P10：磁共振成像 MRI 使用强磁场和无线电波，将原子（主要是人体中的 H2O）引起的信号收集并关联到图像中。通过使用 MRI 技术，医生越来越能够早期诊断出严重的病情（例如，肿瘤），并且早期诊断通常会为患者带来更有利的结果。MRI 测试可提供相对清晰的图像，并使医生可以非常详细地看到身体内部结构。P11:NMR is one of the most powerful analytical tool currently available to an organic chemist.NMR allows characterization of a very small amou
14、nt of sample(5-10mg),and does not destroy the sample(non-destructive technique).Typically NMR is used(in conjunction with other types of spectroscopy and chemical analysis)to fully confirm a complicated molecules structure.P11：NMR 是有机化学家目前可获得的最强大的分析工具之一。NMR 可以表征非常少量的样品（5-10mg），并且不会破坏样品（非破坏性技术）。通常，使用
15、 NMR（结合其他类型的波谱学和化学分析方法）来确定复杂分子的结构。P12:Lets start from the 1H-NMR.1H NMR can tell Us What?Firstly,How many types of H?Indicated by how many groups of signals there are in the spectra Secondly,What types of H?Indicated by the chemical shift of each group And How many H of each type are there?Indicated
16、 by the integration(relative area)of the signal for each group.What is the connectivity?Look at the coupling patterns.This tells you what is next to each group P12：让我们从1H-NMR 的学习开始。1H NMR 可以告诉我们什么？有几种类型的氢原子？由谱图中有多少组信号表示什么类型的 H？由各组的化学位移表示每种类型有多少个 H？用每组信号的积分（相对面积）表示。原子的连接关系是什么？查看耦合方式，获知每个相邻的基团。P13:Wha
17、t Can be obtained in 1H NMR spectra?1.(The Number of Signals)2.(The Position of Signals)3.The Intensities of the Signals 4.The splittings of the Signals Ok,thats todays lecture.Thanks for watching,good-bye!P13：在 1H NMR 光谱中可以得到什么？1.（信号数）多少种不同的 H 核 2.（信号的位置）H 核的化学环境 3.信号强度H 核的数量 4.信号分裂 邻位 H 的数量，类型等 这节课先讲到这里，谢谢收看，再见！