When an NMR spectrum is taken of the molecule below, there is the expected 5H in the aromatic region, triplet (3H) and quartet (2H) upfield of the aromatic region. After adding a drop of acidic D2O, the spectrum changes to one that just has 5H aromatic protons and an upfield 3H singlet. What happens? Explain with mechanisms step by step and include charges and lone pairs of all compounds involved.

When an NMR spectrum is taken of the molecule below, there is the expected 5H in the aromatic region, triplet (3H) and quartet (2H) upfield of the aromatic region. After adding a drop of acidic D2O, the spectrum changes to one that just has 5H aromatic protons and an upfield 3H singlet. What happens? Explain with mechanisms step by step and include charges and lone pairs of all compounds involved.

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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