The paramagnetic shifts of the signals in the 1H NMR spectra by ∼100 ppm downfield with respect to their position in the spectra of uncoordinated ligands were observed.

2024年8月1日 · NMR chemical shift and ppm value chart. The effect of electronegativity and magnetic anisotropy on protons in upfield and downfield regions.

1980年1月1日 · The OCH2 resonances region exhibits a complex pattern (from 4.84 to 4.03 ppm) resulting from the superposition of at least eight quadruplets, while another quadruplet is observed at distinctly higher field (609 = 3.66 ppm, J = 7.2 Hz).

测试核磁时，所用溶剂分子中的氢都应被氘取代，但难免有残余，这样就会产生溶剂峰；除了残存的质子峰外，溶剂中有时会有微量的H2O而产生水峰，而且这个H2O峰的位置也会因溶剂的不同而不同；另外，在样品（或制备过程）中，也难免会残留一些杂质，在图谱上就会有杂质峰，应注意 …

1985年5月15日 · The -OCH2- car- bon signal which occurs in the expected region at -72.0 ppm, along with a sharp 'H NMR resonance at 4.63 due to the -OCH2- groups, demonstrates that the compound contains a dioxo carbene ligand.

From Figure 5, it can be observed that the resonance peaks of H3 and H5 of the furan protons appeared at 7.19 ppm and that at 4.38 is attributed to that of the ester -OCH2 Also observed are two...

In the nmr spectrum of the dianion, the innermost methylene protons (red) give an nmr signal at +22.2 ppm, the adjacent methylene protons (blue) give a signal at +12.6 ppm, and the methyl protons (green) a signal at +5.6 ppm.

为不干扰谱图，所用溶剂分子中的氢都应被氘取代，但难免有氢的残余（1%左右），这样就会产生溶剂峰； 除了残存的质子峰外，溶剂中有时会有微量的 H2O 而产生水峰，而且这个 H2O 峰的位置也会因溶剂的不 同而不同；另外，在样品（或制备过程）中，也难免会残留一些杂质，在图谱上就会有杂质峰，应注意识 别。 以下给出了一些常见溶剂峰和杂质峰的化学位移：

2024年3月8日 · 核磁溶剂峰和杂质峰.docx,常用氘代溶剂和杂质峰在1h-nmr 谱中的化学位移如下表所示（单位：ppm） 溶剂 — cdc13 (cd3)2co (cd3)2so c6d6 cd3cn cd3oh d2o 溶剂峰 — 7.26 2.05 2.49 7.16 1.94 3.31 4.80 水峰 — 1.56 2.84

In the 1H NMR spectrum of PUII (figure 2), peak corresponding to the OCH2 (a) of the PTMG, was observed at 4.06-4.07 ppm. The peak related to the CH 2 (b) of PTMG appeared between 1.62 and 1.63...