Explain why the trimethylsilyl substituents in the allene 2.111 enable the phenyl and the methyl groups to exchange places rapidly, as shown by the coalescence at –90 °C of the signals from the trimethylsilyl groups in the 'H-NMR spectrum. Ar Ar 36 kJ mol-1 B. B. Me;Si Me;Si Me Ph MezSi Ph Me Me;Si B В Ar Ar 2.111a 2.111b

Explain why the trimethylsilyl substituents in the allene 2.111 enable the phenyl and the methyl groups to exchange places rapidly, as shown by the coalescence at –90 °C of the signals from the trimethylsilyl groups in the 'H-NMR spectrum. Ar Ar 36 kJ mol-1 B. B. Me;Si Me;Si Me Ph MezSi Ph Me Me;Si B В Ar Ar 2.111a 2.111b

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 66GP: A 13C NMR spectrum of commercially available 2,4-pentanediol, shows five peaks at 23.3, 23.9, 46.5,...

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