2023年1月30日 · The two peaks at 137 ppm and 129 ppm are due to the carbons at either end of the carbon-carbon double bond. And the peak at 26 is the methyl group which, of course, is joined to the rest of the molecule by a carbon-carbon single bond.

2024年3月20日 · 如何通过核磁氢谱hnmr和碳谱cnmr来确定已知化合物的结构呢？ 下面通过一个实例讲解来说明如何解析氢谱和碳谱，从而确定化合物的结构。 一化合物分子式为C18H19NO4, 1H-NMR和13C-NMR如图1所示 图1 1H-NMR (acetone-…

In general, when you start analyzing a 13 C NMR, split the spectrum in two parts by drawing a line at 100 ppm; below this value you have the saturated functional groups, and beyond that is the unstructured region. Saturated carbon atoms connected to electronegative heteroatoms give signals from 30-90 ppm.

Below is the proton-decoupled 13 C-NMR spectrum of ethyl acetate, showing the expected four signals, one for each of the carbons. While broadband decoupling results in a much simpler spectrum, useful information about the presence of neighboring protons is lost.

INTERPRETING C-13 NMR SPECTRA? This page takes an introductory look at how you can get useful information from a C-13 NMR spectrum. Important: If you have come straight to this page via a search engine, you should be aware that this is the second of two pages about C-13 NMR.

识别杂质峰：在¹H-NMR谱中，溶剂峰是最常见的杂质峰，如氘代甲醇的溶剂峰在3.30 ppm，水峰在4.8 ppm。排除这些峰后，才能更好地分析样品峰。 排除这些峰后，才能更好地分析样品峰。

2021年8月6日 · 再结合碳谱分析，166.4 ppm是酯羰基信号，156.8 - 111.3 ppm是两个苯环和一个双键的碳信号，其中有些对称碳信号重合在一起，其中156.8, 149.2和148.7是连有氧原子的苯环碳信号，56.3 ppm是甲氧基碳信号，42.0 ppm是连N碳信号，35.8 ppm是脂肪碳信号，综上所述，并 …

2025年1月4日 · Learn about carbon-13 NMR spectroscopy for A Level Chemistry, including analyzing chemical shifts and identifying carbon environments.

2023年1月30日 · In C-13 NMR, you cannot draw any simple conclusions from the heights of the various peaks. 1-methylethyl propanoate is also known as isopropyl propanoate or isopropyl propionate. There are two very simple peaks in the spectrum which could be identified easily from the second table above.

Nuclear Magnetic Resonance (NMR) is a commonly used technique for organic compound structure determination. In 13C NMR, applying an external magnetic ield causes the nuclei spin to lip. The environment of the carbon atom in the molecule afects where the signal is seen on the resultant spectrum. CHEMろCAL SHろFT (ﾛ, ppm)