All methyl esters of long-chain aliphatic acids (e.g., methyl tetradecanoate, C13H27COOCH3) show significant fragment ions at m/z 74, 59, and 31. What are the structures of these ions? How are they formed?

All methyl esters of long-chain aliphatic acids (e.g., methyl tetradecanoate, C13H27COOCH3) show significant fragment ions at m/z 74, 59, and 31. What are the structures of these ions? How are they formed?

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter14: Mass Spectrometry

Section: Chapter Questions

Problem 14.37P

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Concept explainers

Mass Spectrometry

This process is an instrumental method in which a sample is changed to fast moving positive ions by electron bombardment. The charged particles vary due to their different mass to charge ratio and are estimated with the help of this difference. It is also called mass spectroscopy.

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All methyl esters of long-chain aliphatic acids (e.g., methyl tetradecanoate, C₁₃H₂₇COOCH₃) show significant fragment ions at m/z 74, 59, and 31. What are the structures of these ions? How are they formed?

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