Use the observed 1H NMR data to decide whether C and its dianion are aromatic, antiaromatic, or not aromatic. C shows NMR signals at –4.25 (6 H) and 8.14–8.67 (10 H) ppm. The dianion of C shows NMR signals at –3 (10 H) and 21 (6 H) ppm. Why are the signals shifted upfield (or downfield) to such a large extent?

Use the observed 1H NMR data to decide whether C and its dianion are aromatic, antiaromatic, or not aromatic. C shows NMR signals at –4.25 (6 H) and 8.14–8.67 (10 H) ppm. The dianion of C shows NMR signals at –3 (10 H) and 21 (6 H) ppm. Why are the signals shifted upfield (or downfield) to such a large extent?

Organic Chemistry

9th Edition

ISBN:9781305080485

Author:John E. McMurry

Publisher:John E. McMurry

Chapter30: Orbitals And Organic Chemistry: Pericyclic Reactions

Section30.SE: Something Extra

Problem 37AP: The 1H NMR spectrum of bullvalene at 100 C consists only of a single peak at 4.22 . Explain.

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Use the observed 1H NMR data to decide whether C and its dianion are aromatic, antiaromatic, or not aromatic. C shows NMR signals at –4.25 (6 H) and 8.14–8.67 (10 H) ppm. The dianion of C shows NMR signals at –3 (10 H) and 21 (6 H) ppm. Why are the signals shifted upeld (or downeld) to such a large extent?
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