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Overview of typical 1H NMR shifts. Note: alkene region modified from earlier handout.
A GUIDE TO 1H NMR CHEMICAL SHIFT VALUES. Nuclear Magnetic Resonance (NMR) is a commonly used technique for organic compound structure determination. In 1H NMR, applying an external magnetic field causes the nuclei spin to flip.
As seen in the 1 H NMR spectrum of methyl acetate (Fig. 6.6a), the x-axis units of the NMR spectrum are in ppm (not in H z, as we would expect for frequency), and the two signals stand at different positions along the x-axis. Let’s explain how that works and what information can be obtained.
1H NMR TIP SHEET. Correlation chart: One peak for each DIFFERENT H. Integration: Tells how many H there are of a given type. For peaks < 5 ppm the following usually applies: 3H = CH3 9H = 3 x CH3 2H = CH2; NH2 (NH2 single peak) 6H = 2 x CH3 OR 3 x CH2 1H = CH; NH; OH (NH, OH single peak) 4H = 2 x CH2.
The simplified proton NMR spectrum of ethanol enables the hydrogen atoms to be easily identified. Notice also that spectra also show the integration of the peaks (the area under each peak). Thus in the spectrum opposite, the smallest peak represents the single H in the OH group (integration of 1)
1.1 Scope and Organization. The present data collection is intended to serve as an aid in the interpretation of molecular spectra for the elucidation and confirmation of the structure of organic compounds. It consists of reference data, spectra, and empirical correlations from.
'able 14.4 Calculation ofÄH NMR Chemical Shifts for Alkenes See Figure 14.12 for more information. as 0.97 0.93 -1.06 -0.65 —0.40 0.37 0.19
