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Progress in Nuclear Magnetic Resonance Spectroscopy
JOURNAL
OF MAGNETIC
RESONANCE
3, 508 (1970)
Book Review Progress in Nuclear Magnetic Resonance Spectroscopy, Volume 5. Edited by J. W. EMSLEY, J. FEENEY, and L. H. SUTCLIFFE. Pergamon Press, Headington Hill Hall, Oxford. 1969. 406 pp. $18.50. This volume is composed of three sections. The first 32 pages are devoted to a lucid discussion of INDOR as it is used in high-resolution NMR snectroscoov. This chanter. bv V. J. Kowalewski. represents a description of the technique, a discussion of the-important principles, and some examples of how it has been applied. The most recent reference is to a 1967 paper, so that it is by no means a summary of achievements to date in the field, but it seems a useful, balanced introduction. The second chapter, by T. H. Siddall and W. E. Stewart, contains 114 pages under the heading, “Magnetic NonEquivalence Related to Symmetry Considerations and Restricted Molecular Motion.” Principal attention is devoted to the matter of measuring rates of such processes as internal rotation or inversion by utilizing the nonequivalence produced by lack of symmetry. A short introduction, covering the circumstances required for this type of nonequivalence, is followed by a discussion of factors affecting rotational rates. It is satisfying to see here some emphasis placed on the often-neglected factor of the de-stabilization of the lowest energy level by steric repulsions, an effect which may reduce a rotational barrier in the same way that, for example, loss of partial double bond character does. A survey of examples follows and then there are sections dealing with inversion about centers like nitrogen or phosphorus, with slow ring inversion, with metal chelates, with a variety of complexes containing inorganic ligands, such as fluorine, and finally with some miscellaneous systems. An interesting feature is a two-page tabulation of kinetic data for rotation in amides, as well as an Appendix which gives a brief discussion of the quality of such data. The third chapter, some 130 pages, is devoted to the applications of proton NMR spectroscopy to conformational analysis of cyclic compounds, but only saturated single-ring systems with three to six members are included. Somewhat surprisingly, there is also a section on a subject related to conformational analysis but not directly within it, and this is the matter of three-membered rings, which are essentially rigid. Within the compass of the review, effort was apparently made to include a comprehensive coverage of all published results. The bibliography of 740 references is quite imposing. However, it is disappointing to find that chapters 2 and 3 of the volume terminate their coverage in 1966 and 1967, respectively, which represents quite a time lag from completion of the literature review to appearance of the volume in late 1969. It is also distressing to find two references in succession, numbers 65 and 66 on page 141, in which initials or names of the authors have been garbled. One wonders how many numerical errors have likewise escaped the attention of the proof readers. Despite these shortcomings, the book is recommended for all high-resolution NMR spectroscopists. WALLACE S.BREY.JR. Department of Chemistry, University of Floridu, Gainesville, Florida 32601
508
OF MAGNETIC
RESONANCE
3, 508 (1970)
Book Review Progress in Nuclear Magnetic Resonance Spectroscopy, Volume 5. Edited by J. W. EMSLEY, J. FEENEY, and L. H. SUTCLIFFE. Pergamon Press, Headington Hill Hall, Oxford. 1969. 406 pp. $18.50. This volume is composed of three sections. The first 32 pages are devoted to a lucid discussion of INDOR as it is used in high-resolution NMR snectroscoov. This chanter. bv V. J. Kowalewski. represents a description of the technique, a discussion of the-important principles, and some examples of how it has been applied. The most recent reference is to a 1967 paper, so that it is by no means a summary of achievements to date in the field, but it seems a useful, balanced introduction. The second chapter, by T. H. Siddall and W. E. Stewart, contains 114 pages under the heading, “Magnetic NonEquivalence Related to Symmetry Considerations and Restricted Molecular Motion.” Principal attention is devoted to the matter of measuring rates of such processes as internal rotation or inversion by utilizing the nonequivalence produced by lack of symmetry. A short introduction, covering the circumstances required for this type of nonequivalence, is followed by a discussion of factors affecting rotational rates. It is satisfying to see here some emphasis placed on the often-neglected factor of the de-stabilization of the lowest energy level by steric repulsions, an effect which may reduce a rotational barrier in the same way that, for example, loss of partial double bond character does. A survey of examples follows and then there are sections dealing with inversion about centers like nitrogen or phosphorus, with slow ring inversion, with metal chelates, with a variety of complexes containing inorganic ligands, such as fluorine, and finally with some miscellaneous systems. An interesting feature is a two-page tabulation of kinetic data for rotation in amides, as well as an Appendix which gives a brief discussion of the quality of such data. The third chapter, some 130 pages, is devoted to the applications of proton NMR spectroscopy to conformational analysis of cyclic compounds, but only saturated single-ring systems with three to six members are included. Somewhat surprisingly, there is also a section on a subject related to conformational analysis but not directly within it, and this is the matter of three-membered rings, which are essentially rigid. Within the compass of the review, effort was apparently made to include a comprehensive coverage of all published results. The bibliography of 740 references is quite imposing. However, it is disappointing to find that chapters 2 and 3 of the volume terminate their coverage in 1966 and 1967, respectively, which represents quite a time lag from completion of the literature review to appearance of the volume in late 1969. It is also distressing to find two references in succession, numbers 65 and 66 on page 141, in which initials or names of the authors have been garbled. One wonders how many numerical errors have likewise escaped the attention of the proof readers. Despite these shortcomings, the book is recommended for all high-resolution NMR spectroscopists. WALLACE S.BREY.JR. Department of Chemistry, University of Floridu, Gainesville, Florida 32601
508