Review of Spectrometric Identification of Organic Compounds, 8th Edition

Abstract

The organization of the 8th edition is the same as that of 7th edition, and consists of seven chapters. Chapter 1 presents the technique of mass spectrometry. This chapter is virtually the same as that of the previous edition. The initial portion of the chapter is devoted to instrumental techniques such as ionization methods, mass analyzers, Fourier transform mass spectrometry, and tandem mass spectrometry. The remaining portion of the chapter gives an overview of fragmentation patterns of common organic homologous series. This portion of the chapter gives all the necessary background for understanding organic EI and CI mass spectrometry. For those students who want to go deeper into strategies of data interpretation and fragmentation patterns, J. T. Watson’s and F. W. McLafferty’s books are two valuable references. Surprisingly, there is hardly any discussion on isotopic patterns of poly-halogenated compounds. Except for the two additional sections on polymer and phosphorus compounds, Chapter 2 on infrared spectroscopy remains the same as that of the last edition. After initial presentation of the Michelson interferometer, sample handling, and coupled vibrations, the remaining portion of the chapter covers characteristic vibrations of various organic groups. The discussion on characteristic frequencies is extensive and useful in confirming the presence of organic functional groups in a given molecule. The next four chapters focus on NMR spectroscopy. Naturally, the first of these four chapters covers proton NMR spectroscopy. In this chapter, all the basic theories, concepts and terminologies such as free induction decay, relaxation, chemical shifts, scalar coupling, Pople notation, and chemical and magnetic equivalence are introduced. A few sections have been completely revised. The treatment of chemical equivalence has been shortened and revised. The exposition of this concept is better than that of the 7th edition. The section on the analysis of a complex first-order spectrum, although remaining largely the same as that of the previous edition, is well presented and provides a tool for analyzing this type of spectra methodically. In summary, this chapter covers proton NMR and all the necessary background for the subsequent three chapters. A few sections in the chapter on carbon-13 NMR have been revised. This chapter mainly covers all the topics such as chemical shifts (various functional groups), T1 relaxation, phase inversion recovery, broadband decoupling, gated-decoupling technique, nuclear Overhauser effect (NOE) and DEPT. NOE is only introduced in the context of signal enhancement or depletion. No discussion on the physics behind NOE is covered. Conceptually, this is the easiest among the four NMR chapters. Part of the chapter on two-dimensional NMR has been rewritten to make it much clearer and up-to-date. All current two-dimensional NMR techniques such as DQF-COSY, HETCOR, HMQC, HMBC, INADEQUATE, TOCSY (1-D and 2-D), and ROSEY are presented. HSQC, a variant of HMQC, is not covered. This is not a book for one trying to learn the principles behind pulse sequences. For those who want to have a better understanding of the principles behind pulse sequences, Friebolin’s and Claridge’s books should be consulted. The original section on pulse field gradient has been revised to include brief discussions on techniques such as ultrafast multidimensional NMR and single-scan NMR. Four compounds, namely, ipsenol, caryophyllene oxide, lactose, and the tetrapeptide VGSE (valine, glycine, serine, and glutamic acid) are used to illustrate the use of 2-D technique for structural elucidation. It starts with the easiest molecule, ipsenol, and ends with a more complicated one, VGSE. Each structure is derived from the given spectra in a systematic way. This part of the chapter remains largely the same as that of 7th edition. To understand how a structure is determined, one has