3. Consider the structure of N,N-dimethylformamide (DMF, seen below). We might expect the two methyl groups to be equivalent; however, both the proton and carbon NMR spectra of DMF show two separate signals for the methyl groups. Propose an explanation for the nonequivalence of the methyl groups. (HINT-Consider the resonance contributors of this compound) Should be CH3 Hi CH3

3. Consider the structure of N,N-dimethylformamide (DMF, seen below). We might expect the two methyl groups to be equivalent; however, both the proton and carbon NMR spectra of DMF show two separate signals for the methyl groups. Propose an explanation for the nonequivalence of the methyl groups. (HINT-Consider the resonance contributors of this compound) Should be CH3 Hi CH3

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter13: Structure Determination: Nuclear Magnetic Resonance Spectroscopy

Section13.SE: Something Extra

Problem 56GP: Long-range coupling between protons more than two carbon atoms apart is sometimes observed when ...

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