Proton NMR Table - MSU Chemistry

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This page has tables of 1H Chemical Shifts and 13C Chemical Shifts.

Proton Chemical Shift Ranges*

Proton Chemical Shifts
*For samples in CDCl3 solution. The d scale is relative to TMS at d=0. Organic ChemistryMichigan State University

The broad ranges shown at the bottom of the chart (orange color) are typical of hydrogen bonded protons (eg. OH and NH). These signals are concentration and temperature dependent. Note that in DMSO-d6 solution, alcohol OH signals are shifted to lower field (d 4.0 to 6.0ppm), and usually display vicinal coupling.

Inductive deshielding effects of electronegative substituents are roughly additive, as the following data suggests.

    Proton Chemical Shifts (ppm)
    Cpd./Sub. X=Cl X=Br X=I X=OR X=SR
    CH3X 3.0 2.7 2.1 3.1 2.1
    CH2X2 5.3 5.0 3.9 4.8 3.8
    CHX3 7.3 7.0 5.7 5.2

Furthermore, the longer-range influence of such substituents is apparent (although diminished) in compounds such as CH3-CCl3, d = 2.72 ppm, and CH3-C(OR)3, d = 1.46 ppm.

Anisotropic effects are common in p-electron systems, and are often responsible for atypical chemical shifts. For example:

Annulene Cyclophane
The 14 p-electron bridged annulene on the left is an aromatic (4n + 2) system. It forms a dianion which is a 16 p-electron (4n) system. 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.

Carbon Chemical Shift Ranges*

Carbon Chemical Shifts
*For samples in CDCl3 solution. The d scale is relative to TMS at d=0. Organic ChemistryMichigan State University

Conjugation of a double bond with a carbonyl group perturbs the carbon resonances of both groups. The b-carbon of the double bond is shifted to lower field by 20 to 30 ppm, and the carbonyl carbon is shifted to higher field by 5 to 15 ppm.

Examples of the effect of multiple substituents on a carbon atom are shown in the following table. Halogen substitution effects are complex, with fluorine and chlorine generally shifting the carbon resonance to lower field, but iodine having an opposite influence.

    Carbon Chemical Shifts (ppm)
    Cpd./Sub. X=F X=Cl X=Br X=I X=OMe
    CH3X 75 25 10 -21 60
    CH2X2 110 54 22 -54 103
    CHX3 119 77.5 12 -140 115
    CX4 94 97 -29 -293 121
Click here to access an outstanding nmr data resource provided by the University of Potsdam .

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