This book, a revised translation of a successful German work, is a compilation of data for the spectroscopic methods most widely used for the structural elucidation of organic molecules, viz. 'H NMR, 13C NMR, IR and UV/visible spectroscopy and mass spectrometry. It updates and extends the information provided by such standard works as those of Bellamy on IR group frequencies and of Jackman and Sternhell on ' H NMR, and assembles in a single volume data which have hitherto been available mostly in separate specialised texts.The book is divided into six sections of comparable length, within which data are presented in well organized tables or annotated structural diagrams. Further information is provided by appended comments and short notes.The first section summarizes the structural information which may be derived from the presence of signals in particular spectral regions, while a series of combination tables collates all spectroscopic data according to compound type and gives references to the remaining five sections, in which in-depth coverage is given to each technique in turn.The ' H and 13C N M R sections list chemical shifts and coupling constants (lH-lH, 'H-13C and couplings of 'H and 13C with common heteronuclei) for compounds ranging from simple alkanes to condensed heteroaromatics. Rules for the prediction of these parameters are described and spectra of common NMR solvents are shown. The W/visible section includes a table of A, , and em, values for a wide range of simple chromophores and illustrates the use of the Woodward and Scott rules for Am= prediction. Also provided is a useful catalogue of reference spectra for common chemical structures. A comprehensive table of group frequencies arranged by chemical structure forms the basis of the IR section; the associated comments are particularly informative. A short discussion of interferences in IR spectra is given and spectra of common IR solvents and suspension media are shown. Mass spectrometry coverage, confined to 70 eV EI spectra, includes a table of assignments and parent molecules for ions of up to 167 mass units. Other information includes isotope patterns for all natural elements, spectra of common solvents and contaminants and a short discussion of metastable peaks.While not replacing the established spectroscopic texts, this book provides a wealth of information at a comparatively modest price and will appeal to the more committed student. It will also be a valuable reference work for any laboratory combining spectroscopic methods for the determination of chemical structure. As a consequence of its integrated approach, the specialist reader is exposed to the advantages of other techniques and, in this respect, the re-emphasis on the somewhat neglected structural uses of UV/visible spectroscopy is particularly appropriate. The absence of any discussion on the newer ionization methods for mass spectrometry is unfortunate, and it is to be hoped that this omission will be rectified in subsequent editions.The text is logically organized and we...

Fig. 1 illustrates a definition of the terms endocyclic and exocyclic SN‐reactions, referring to intramolecular nucleophilic substitution processes that occur by an SN2‐analogous mechanism. Crossing experiments show that the methyl transfer I → II (see scheme 1) does not follow the formally appealing mechanism of the endocyclic SN‐process III; the reaction proceeds intermolecularly under all conditions investigated. Kinetic measurements indicate that the methyl transfer XI → XII (see scheme 3) occurs in a similar fashion. This behaviour is believed to follow from the preference of tetrahedral carbon for backside attack by the nucleophile in SN2‐reactions. The general experience, according to which intramolecular reaction paths over cyclic transition states with ring sizes of 5 or 6 are preferred to their intermolecular counterparts, is not to be extrapolated to SN2‐reactions at tetrahedral carbon.

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