The structures and reactions of the aromatic compounds

EVER since Kekul4 made his clarsic suggestion for the structure of benzene a tremendous volume of theoretical and experimental evidence has been amass...
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THE STRUCWRES AND REACTIONS OF THE AROMATlC COMPOUNDS

The chapter titles indicate, a t least partially, the scope of the book: The Benzene Problem; Some Properties of Aromatic Compounds; Addition Reactions of Aromatic Compounds; G. M.Badger, Reader in Chemistry in the University of Adelaide. The Aromatic "Double Bond"; The Effects of Substituents; 456 pp. Aromatic Substitution Reactions; The Diels-Alder Reaction; Cambridge University Press, New York, 1954. xii Many figs. and tables. 14.5 X 22 cm. $11.50. Absorption and Photo-Oxidation and Photo-Dimerization; Fluorescence Spectra of Aromatic Compounds; Optical Activity EVERsince Kekul4 made his clarsic suggestion for the structure in Arom~tieCompounds. of benzene a tremendous volume of theoretical and experimental Once in a while the text gives the impression that the author evidence has been amassed in an attempt to ascertain the actual has attempted to compress afield too large into a space too small. structure of benzene and its dose relatives, the more common For the most part, however, the author is quite successful in his aromatic hydrocarbons. Now, after nearly one hundred years, our conception of the structure of benzene is more rational, and rather courageous venture in writing such a book. There are a. few undoubtedly more nearly correct, than the proposal of KekulP. occasional statements which, because of brevity, may be someOf all the structural problems in organic chemistw. the structures what misleading. One appears on page 250: "Benzene, chloroare not methyhted under beuzene, toluene, and naphthalene. of the aromatic ccoipounds are perhaps the &st fascinating. the same conditions but give the normal direct oxidation product.'' It seems quite reasonable that an organic chemist should be The text appears to be almost entirely free of typographical errors. sufficiently fascinated to survey the field of structural aromatic This book merits the attention of all teachers of organic chemistry and to then compile this information in textual form. chemie?;; Advanced underzaduat? 5" (!.+duate studczk nr.5ads:i no'&.& pa! ~ P B ~ # C ~ Bask D ~ R iIh ~a & ' " & j e e i $ l ~ ~ m wiii it v extremely %'ormstive &rid liieid. ~ 0 wig has many uangers," and that often "it becomes more and more surely be an invaluable addition to every library. difficult to see the wood for the trees." He seem? to he an exDONALD C. GREGG cellent "woodsman." He is aware that the "trees" differ in size, variety, and individual significance within the "wood." He also appears quite able to recognize each "tree's" current degree of maturity. Most readers will agree that he has written this volume in a remarkably dispassionate manner. The organization of the material follows a commendable pedagogicd pattern. In the major, individual sections the problem is hlTRODUCTlON TO CHEMISTRY stated first, then the experimental evidence, and finally the current, theoretical solution. Most of the book is descriptive, but R. T. Sanderson, Professor of Inorganic Chemistry, State Unimany examples are given in certain sections to clarify the over-all versity of Iowa. John Wiley & Sons, Inc., New York, 1954. x picture. Ample references are made to the original literature. 542 pp. 61 figs. 24 tables. 15 X 22 cm. $5.50. Because the title of the book may be misleading to some poTHE number of general-chemistry texts available increases tential readers, it should be noted that the author has placed definite boundaries on his material. Certain "less important sub- yearly. Not only are most of the better-known texts appearing stitution reactions" have not been included. Synthetic methods as revisions, but also an increasingly large number of first editions have been omitted, except for a few which involve direct sub- are on the market. The majority of recent texts are characterized by the inclusion stitution or addition to an aromatic nucleus. Very few side reactions are discussed, and then usually to explain the effects of large amounts of fundamental material regarding nuclear, produced by nuolear substituents or to indicate the nature of atomic, and molecular structure. Many of these texts also coninduct,iveand mesomerio effects. Much of the more recent work tain sections dealing with metallurgy, electrochemistry, organic on tropolono and an the Friedel-Crafts reaction could not be in- chemistry, and the chemistryof macromolecules. In fact, they are cluded, unfortunately, because the reports were published after compendia of the science, chemistry. Such texts are in most eases the author had completed the text. For the most part, references excellent for students who have had above-average training to the literature are not later t,han the middle of 1951. In essence, in secondary-school chemistry or are in a class screened by prethe book is mainly concerned with the apparent electronic struc- requisites or placement tests. Such texts are also valuable as tures of the common, aromatic nuclei and the reactions which references during the students' college careers. However, the vast amount and, in some e m s , complexity of the subject matter directly involve these aromatic nuclei. in these texts often frustrates the students and makes a. "tough" The problematical existence of the so-called aromatic "double" bond is treated quite aptly. The discussion of the structure of subject appear tougher. This text is not one of the aforementioned type. It is signilinaphthalene relative to the evidence for a "double" bond at the 1-2 position and a "single" bond at the 2-3 position is exception- cant in its simplicity of style, completeness of fundamental mateally good. Students who read this book will surely beimpressed rial, and candor in omission of most of the material which by the manifold evidence far the present concept of the exeep- probably would not he covered in the elementary course. The tianal electronic mobility of the so-called hybrid state of an a m - author's avowed purpose was to write a text ". . . long on exmatic nucleus. Students will also appreciate the fact that the planation and short on purely descriptive chemistry." He electrons in the hybrid may be localized, more or less, by the states: "I see no reason why the lecture cannot be supplementary presence of another substance, and especially a t the instant be- to the textbook rather than the textbook supplementary to the fore a chemical reaction. With this realization in mind, the lectures. If the textbook contains only what the students should thoughtful student should not be unduly confounded when he is learn then they can study it at leisure and with confidence!' told that both nucleophilic and electrophilie substitution on For thme teachers who subscribe to such a philosophy, this text should prove to be a happy choice. naphthalene occur most. frequently a t the 1-position.

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