大学化学 >> 2025, Vol. 40 >> Issue (10): 203-207.doi: 10.12461/PKU.DXHX202411076

化学实验 上一篇    下一篇

在自然丰度下的动力学揭秘:13C NMR同位素效应实验

张文文, 张培超, 盖聪昊, 柴晓云, 邹燕, 赵庆杰   

  1. 海军军医大学药学系有机化学教研室, 军事药学实验教学示范中心, 上海 200433
  • 收稿日期:2024-11-21 录用日期:2025-04-03 发布日期:2025-09-17
  • 通讯作者: 赵庆杰 E-mail:qjzhao@smmu.edu.cn

Unveiling Kinetics at Natural Abundance: 13C NMR Isotope Effect Experiments

Wenwen Zhang, Peichao Zhang, Conghao Gai, Xiaoyun Chai, Yan Zou, Qingjie Zhao   

  1. National Demonstration Center for Experimental Military Pharmacy Education, Department of Organic Chemistry, School of Pharmacy, Naval Medical University, Shanghai 200433, China
  • Received:2024-11-21 Accepted:2025-04-03 Published:2025-09-17
  • Contact: Qingjie Zhao E-mail:qjzhao@smmu.edu.cn

摘要: 在化学反应动力学研究中,动力学同位素效应(KIE)为深入理解化学反应路径和机制提供了关键信息。除了广泛应用的氢/氘同位素效应外, 碳原子以及质量更大一些原子的同位素效应也日益受到关注。值得一提的是, Singleton于1995年提出了一种基于核磁共振(NMR)技术的高精度KIE (12C/13C)测量方法,为该领域带来了重要突破。该方法无需对化合物进行昂贵且复杂的同位素标记操作,利用13C的自然丰度的样品结合高分辨率NMR实验,能够直接测量12C和13C之间的KIE数值,且具有极高的精度。本文将详细介绍这一方法的理论基础、实验步骤以及应用实例,探讨其在化学反应机理和动力学研究中的重要意义与优势。

关键词: 动力学同位素效应(KIE), 核磁共振(NMR)技术, 自然丰度, 13C NMR同位素效应实验, 化学反应机制

Abstract: In chemical reaction kinetics studies, kinetic isotope effects (KIE) provide critical information for understanding reaction pathways and mechanisms. While hydrogen/deuterium isotope effects have been extensively studied, increasing attention is being paid to isotope effects involving carbon and other heavier atoms. A significant breakthrough occurred in 1995 when Singleton developed a high-precision NMR-based method for measuring 12C/13C KIE values. This innovative approach eliminates the need for expensive and complex isotope labeling procedures. By utilizing samples with natural 13C abundance and high-resolution NMR spectroscopy, the method enables direct measurement of 12C/13C KIE values with remarkable precision. This article comprehensively describes the theoretical foundations, experimental protocols, and practical applications of this method, emphasizing its importance and advantages in mechanistic and kinetic studies of chemical reactions.

Key words: Kinetic isotope effect (KIE), Nuclear magnetic resonance (NMR) technology, Natural abundance, 13C NMR isotope effect experiment, Chemical reaction mechanism