Book Review Phase Transfer Catalysis. Selected Problems and Applications. By Y. Goldbergкод для вставкиСкачать
BOOKS A Broad Base from Theory to Applications Cluster Ions. (Wiley Series in Ion Chemistry and Physics.) Edited by C-I: N g , 7: Baer and I. Powis. Wiley, Chichester, 1993. 479 pp.. hardcover E 80.00-ISBN 0-471-93830-0 This book contains a survey of recent developments in fundamental research on cluster ions. It consists of seven chapters, mostly concerned with van der Waals clusters, although carbon and silicon clusters are also included. The title is in fact too broad. suggesting to the reader that metal clusters are also covered. First W. Kamke describes cluster studies using the photoelectron-photoion coincidence (PEPICO) technique, dealing both with the experimental aspects and with applications to van det- Waals systems. This method is very effective for recording photoelectron spectra of sizeselected neutral clusters, especially when applied with electrons of zero kinetic energy (threshold photoelectrons, TPE). The use of the technique is illustrated by examples. such as studies of the unimolecular decay of noble gas clusters, charge transfer in mixed clusters, and ionmolecule reactions in ammonia clusters. The next chapter by C. Lifshitz is concerned with the unimolecular and collision-induced decomposition of protonbound clusters and carbon cluster ions. F o r the first of these ion types, with the general formula H '(MJ, excitation typically results in a solvent molecule M being This Section contains book reviews and a list of new books received by the editor. Book reviews are written by invitation from the editor. Suggestions for hooks to be reviewed and for book reviewers are welcome. Publishers should send brochures or (better) books to Dr. Ralf Bauniann, Redaktion Angewandte Chemie, Postfach 10 11 61. D-69451 Weinheim. Federal Republic ofGermany. The editor reserves the right of selecting which books will be reviewed. Uninvited books not chosen for review will not be returned. A n g i w . Clwm. Inr. Ed, EngI. 1994, 33, No. 15/16 "evaporated" off within a few microseconds. By measuring the kinetic energies of the ejected molecules one can determine bond energies, and collision-induced dissociation reveals isomeric structures. The section on carbon clusters deals particularly with the currently fashionable fullerenes C&, C&, and C& and their novel chemistry. In Chapter 3 M. F. Jarrold describes the many unique features of the physics and chemistry of positive and negative silicon cluster ions. The author has worked intensively in this field, using a variety of experimental methods to obtain the fullest possible information. Some of his results from drift-tube measurements are in striking disagreement with those obtained by Smalley's group using Fourier transform ion cyclotron resonance; the reason for this discrepancy is not yet known. The fourth chapter by J. M. Lisy describes vibrational spectroscopic studies of solvated proton and metal ion clusters which serve as models for dilute electrolyte solutions. An interesting result is that proton clusters generated in a corona discharge are relatively cold, and consequently more than one infrared photon is needed for dissociation, whereas the metal ion clusters, which are produced by association and are relatively warm, are dissociated by only one CO, laser photon. Next (Ch. 5) J. M. Farrar reports on the electronic photodissociation of mass-selected van der Waals clusters. mainly with regard to the influence of solvation on this process. The closer one approaches to the condensed phase, i.e. the greater the number of solvent molecules attached to the central ion, the further the absorption is shifted towards the infrared. Measurements of this effect are reported for several systems; for example,'the addition of up to six ammonia molecules to Sr' shifts the absorption maximum from about 400 nm to about 1400 nm. However, the number of ligands is still insufficient to simulate the transition from gas phase clusters to the liquid phase. Noble gas clusters are the subject of Chapter 6, by I. Last and T. F. George, then in the final chapter B. G . Brunetti and F. Vecchiocattivi report on autoionization dynamics of collision complexes. In a typical experiment VCH Verlugsgrsrllrcliafi mbH, 0-69451 Weinhrim, 1994 noble gas atoms are excited into metastable states by electron impact, then atoms of a single metastable species are selected by optical excitation and are allowed to collide with a reaction partner under thermal conditions. Whereas the average time needed for a collision is about s, autoionization takes place in about s. After describing the experimental technique the authors discuss applications involving hydrogen. mercury, alkali metal, and noble gas atoms, and molecules such as N,, CO. CI,, H,O, and even CF,CI. The individual chapters are carefully written, and the authors are acknowledged experts in the areas covered. I greatly enjoyed reading the book and can recommend it unreservedly to other physical chemists in the field. Munfrcd P.Irion lnstitut fur Physikalische Chemie der Technischen Hochschule Darmstadt (FRG) Phase Transfer Catalysis. 3rd Revised and Enlarged Edition. By E. IY Dehmlow and S. S. Dehmlow. VCH Verlagsgesellschaft, Weinheim/VCH Publishers, New York, 1993. 499 pp., h a r d c o v e r DM 188.00, $ 125.00--ISBN 3-527-28408-7/1-56081-206-0 Phase Transfer Catalysis. Selected Problems and Applications. By Y Goldbevg. Gordon and Breach, L o n g h o r n e , PA, 1993. 456 p p . , hardcover $ 170.00 ($95.00 if ordered from t h e publishers by private individuals).-ISBN 2-88124-870-5 Phase transfer catalysis (PTC) has nowadays become an indispensable tool for organic synthesis. Many reactions can be carried out more efficiently and selectively by this method, and others for which it has been used were not even possible previously. The above book by Dehmlow and Dehmlow replaces the second edition published ten years ago, having been updated and, where necessary. revised. It includes many new developments in PTC. 057(1-0833.'94:1515-166Y 3 iO.OO+ .75/0 1669 The literature coverage now extends to mid-1990, while at the same time some outdated references have been dropped. There are 1700 new literature citations, bringing the total to over 3600. now listed (unlike the earlier editions) in alphabetical order. The subject index too is a valuable aid when working with this book. Goldberg‘s book on the same subject is based on one originally published in Russian in 1989. which has been revised and updated for this English version. It contains about 1300 literature references extending up to 1991. The subject index. which is mainly substance-orientated, is a useful working aid. The book by Dehmlow and Dehmlow begins with two chapters of more than 60 pages altogether on the theoretical basis of PTC. The first chapter is mainly concerned with the principles underlying the effectiveness of the most important types of catalysts, while the second deals with the mechanistic aspects of the different variants of the PTC method. Chapter 3 (over 300 pages long) is concerned with synthetic applications of PTC. It begins with a section on the choice of reaction conditions, such as the type and quantity of catalyst, the solvent, and the stirring rate. Particular attention is given to enantioselective PTC, describing its applications, problems. and the many potential sources of error. Next the authors describe various practical applications of PTC, arranged so far as possible according to reaction types. These include substitutions leading to alkyl halides, nitriles, esters, thiols. sulfides. and ethers. N - and C-alkylations, alkylations and acylations of ambidentate anions, isomerizations, H / D exchange reactions. and additions at C = O and C = N bonds. Also treated in detail are r-, p-, and y-elimination reactions, the preparation of phosphonium and sulfonium ylides. nucleophilic aromatic substitutions, applications of PTC to organometallic compounds. and reducrims and oxidations. I t is pleasing to find that as well as giving well-proven synthetic recipes the authors include general principles that have been derived for carrying out various types of transformations under phase transfer conditions. The large amount of factual information is very clearly presented. often in the form of tables. enabling the reader not only to quickly find specific details but also to get an overview of a chosen area. Goldberg’s book differs considerably from that of Dehmlow and Dehmlow. both in emphasis and in structure. A first chapter (24 pp.) dealing with the theoretical fundamentals is followed by several chapters describing some selected areas of application of PTC. Chapter 2. the longest in the book with about 100 pages. is concerned with PTC in the chemistry of N-heterocycles. Alkylations and acylations of compounds of this class are described, as also arc reactions of halogenated N-heterocycles with nucleophiles. Reactions of N-heterocycles with carbenes are treated next, followed by oxidations and reductions, as well as the use of PTC in the preparation of such compounds. In Chapter 3 (about 50 pp.). on PTC in organometallic chemistry, much attention is devoted to reactions iiivolving organosjlicon compounds; other reactions discussed include those of mercury. molybdenum, tungsten, iron, cobalt, and platinum compounds. Chapter 4 (about 70 pp.) is devoted to catalysis by metal complexes under phase transfer conditions, including reductions, oxidations. dehydrogenations, and carbonylations. Chapter 5. on three-phase catalytic reactions (about 30 pp.), discusses the advantages and disadvantages of using quaternary onium salts. crown ethers. or open-chain polyethers immobilized on polymers or other substrates for a variety of reactions. In Chapter 6. on asyminetric phase transfer catalysis (about 50 pp.), Goldberg discusses in great detail a number of types of reactions for which PTC has proved more or less successful. He also analyzes a number of experiments that failed completely and were thus of no interest for synthetic purposes, and identifies the factors that previously led to wrong interpretations. These latter discussions are extremely valuable for any chemist intending to apply PTC to asymmetric syntheses for the first time. However. reactions giving optical purities of 15-19% should not be regarded as satisfactory, as is implied on page 299. Chapter 7 (about 40 pp.) is concerned with less common variants of PTC; here the author discusses cationic reactions, reactions at phase boundaries between neutral species. inverse PTC, electron phase transfer, and reactions under the influence of ultrasonic excitation at phase boundaries. The book by Dehmlow and Dehmlow is a standard work on PTC. affording the reader a comprehensive overview ranging from the theoretical fundamentals to the diverse wealth of practical applications of this useful method in synthetic chemistry. It is an indispensable monograph for every chemist. being suitable not only for organic chemists with experience of PTC but also for those about to use this method of synthesis for the first time. Goldberg’s book does not give such a comprehensive picture. nor was that the author’s aim. Instead it is intended for specialists. Because of this quite different approach it may be regarded as complementary to the Dehmlow and Dehmlow monograph. extending the subject and treating it in greater depth, with detailed discussions of many applications of PTC. At some points one might say that it gives too much information-for example, the details given beside the reaction arrows of the synthesis schemes. In both books the subject matter is clearly arranged, in a readable style, and in a sturdy binding. No library should be without them. Fritz Theil Institut fur Angewandte Chemie Berlin-Adlershof (FRG) Fundamentals of Nuclear Magnetic Resonance. By J. W Hennel and J. Klinowski. Longman, Harlow (UK), 1993. 288 pp., paperback f 22.50.ISBN 0-582-06703-0 In their preface the authors formulate their aim: it is to explain the physical and mathematical basis of NMR sinTp/y but exactly. In a certain sense they succeed. However, the question is: what m e the fundamentals of nuclear magnetic resonance? In the opinion of the authors they are the magnetic dipole moment (of a compass needle, a current loop. an orbiting electron, or a nucleus with a spin), the magnetization of a macroscopic sample in thermodynamic equilibrium. the Larmor precession of an isolated spin, Bloch’s equations, the Fourier transformation, the Zeeman and dipolar parts of the Hamiltonian. the method of (second) moments, and the spin-echo and COSY experiments. Sure, all these topics are fundamentals of NMR. and I would regard it as almost a moral obligation of all those who practise N M R to be thoroughly familiar with fundamentals of this kind. It may well be the experience of Jacek Hennel and Jacek Klinowski that only too many are not. And I must admit that the authors’ overview and judgement are very likely quite correct. Therefore, let us admit that there is a need to explain such fundamentals simply and exactly. Does the book fulfill the promise? It starts with a chapter of 42 pages on the “Elements of Quantum Mechanics”. It is supplemented by five appendices explaining topics from “Complex Numbers” to “Sinusoidal Operators.” This is now the third recent book on N M R which I have read in which the authors assume, on the one hand, that they must provide an introduction to complex numbers and.