Spectroscopic Methods in Organic Chemistry

Abstract

This book is the seventh edition of a well-established introductory guide to the interpretation of the mass, ultraviolet, infrared and nuclear magnetic resonance spectra of organic compounds.It is a textbook suitable for a course in the application of these techniques to structure determination and as a handbook for organic chemists to keep on their desks throughout their career.These four spectroscopic methods are used routinely to determine the structure of organic compounds.Every organic chemist needs to be skilled in how to apply them and to know which method works for which problem.In outline, the mass spectrum gives the molecular formula, the ultraviolet spectrum identifies conjugated systems, the infrared or Raman spectrum identifies functional groups and the nuclear magnetic resonance spectra identify how the atoms are connected.One or more of these techniques are frequently enough to identify the complete chemical structure of an unknown compound.If they are not enough on their own, there are other methods that the organic chemist can turn to: X-ray diffraction, microwave absorption, electron spin resonance, atomic force spectroscopy and circular dichroism, among others.Powerful though they are, these techniques are all more specialised and less part of the everyday practice of most organic chemists.In preparing this edition, I have moved the chapter on mass spectrometry to be the first, in order to reflect its importance in giving a molecular formula-a vitally important first step in a structure determination.Along with the following chapters on UV and IR spectra, it remains concise, to reflect the lesser importance of all these techniques, with the discussion of the theoretical background kept to a minimum, since application of spectroscopic methods is possible without a detailed command of the theory behind them.Benefitting from my experience teaching the subject over the last 7 years, I have completely rewritten the chapter on NMR spectroscopy, dividing it into two to separate the discussion of 1D spectra from the 2D spectra.In addition, I have greatly expanded the text with explanations of the spin physics that the earlier edition entirely lacked.I have introduced each of the pulse sequences, and the vector description of the resultant magnetisa-CRY page is updated for previous edition information.