George Olah and coworkers reported a relative of COT shown above, 1,4- dimethylcyclooctatetraene dication. The 'H NMR shows a set of 3 signals with relative integrations of 2:1:3 at 9.96 (two overlapped peaks), 9.90, and 3.98 ppm chemical shift. Explain why the signals at 9.96 and 9.90 show such a low field chemical shift (hint: it is not alone sufficient to say this is due to the positive charge). Second hint: use the r MO diagram you created in part a. to help answer this.

George Olah and coworkers reported a relative of COT shown above, 1,4- dimethylcyclooctatetraene dication. The 'H NMR shows a set of 3 signals with relative integrations of 2:1:3 at 9.96 (two overlapped peaks), 9.90, and 3.98 ppm chemical shift. Explain why the signals at 9.96 and 9.90 show such a low field chemical shift (hint: it is not alone sufficient to say this is due to the positive charge). Second hint: use the r MO diagram you created in part a. to help answer this.

Organic Chemistry: A Guided Inquiry

2nd Edition

ISBN:9780618974122

Author:Andrei Straumanis

Publisher:Andrei Straumanis

ChapterL4: Proton (1h) Nmr Spectroscopy

Section: Chapter Questions

Problem 3E: Here are proton NMR data for 1-bromopropane: Ha : triplet (2H) 3.32ppm; Hb : multiplet (2H)1.81ppm;...

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