Microscale Organic Laboratory (Mayo, DW; Pike...
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Mlcrcecaie Organic Laboratory 0. W. Mayo. R. M. Pike, and S. S. Bvrcher. Wiley: New York. NY. 1986.xix 427 pp. Figs. and tables. 22 X 28.5 cm. $25.95.
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Occasionally a hook appears that makes us reexamine the way we teach chemistry. Microscale Organic Laboratory is one of those provocative hooks. Many instruetors have developed mieroseale experiments that have appeared in this Journal and elsewhere. In most cases these experiments serve as isolated examples of microscale techniaues. In Microscale Oreanic Lobora" lory, however, microscale techniques hecome e way of life. An entire full-year urganic laburatory cwrse has been developed using microscale a n d semimicroscale techniques. My first reaction to an exclusively microscale course was to question whether the chemistrv is watered down to accommodate the mier&eale techniques. I was surp&d to find that the microscale techniques have been adapted to accommodate all the chemistry that is normally covered in the laboratory course, as well as a number of reactions that might he considered too expensive or too dangerous for student use on a larger scale. In each experiment the products are purified and their structures are confirmed, usually by IR spectroscopy. A few of the reactions covered include horohydride and diborane reductions, catalytic hydrogenation, hydroboration, heterocyclic syntheses, use of polymer-bound reagents, NBS halogenation, photochemical isomerization, enzymatic resolution, qualitative analysis, use of protecting groups, and Grignard, Wittig, and Diels-Alder reactions. Given that the coverage of chemistry is excellent, these mieroseale experiments offer several obvious advantages. 1. Safety. On such a small scale, the reagents present a much smaller hazard when they escape or catch fire. Reactions are less Likely to get out of control because of their small volumes and relatively large surface areas. 2. Cost Reduction. The authors conservatively claim 15%to 9 W savings in chemical ccats, accompanied by similar savings in disposal costs. The cost of the microscale glassware and equipment is similar to that for the standard ground glass kits in use. 3. Technique. The small scale involved in these experiments promotes careful
techniaue. esoeciallv in transferrine materrals 'k;w&n combinen. These'& niques should prove valuable in analyficsl work and in advanced stages of ayntheses. 4. Speed. Because the microscale techniques take less time, students can complete more reactions than they can using preparative-scale reactions. Therefore, this hook covers a wider range of chemical reactions than most traditional organic laboratory manuals. The pure microscale approach is not without its drawbacks, however. Some of the most common lahoratory techniques cannot he demonstrated effectively using microscale equipment and techniques. For examole. ~. downward distillation is never encountered: a Hickman still head is usrd, and the distillate is removed using apipet. Frartional distillatim ia simulated by using three separate distillations to get a two-plate separation of hexane and toluene. A separatory funnel is never used, because small volumes are more easily handled in a conical vial with separation accomplished using a pipet. These omissions lead to my major reservation about the exclusive use of microscale experiments in the organic laboratory. Professional chemists and chemical engineers must know how to run preparative reactions. Drugs must he synthesized in quantities for clinical trials, monomers must be synthesized in bulk to test polymer properties. and the first few stem of a lone svnthe~~~~.~~ sis may require lage-scale reaction.. If we don't teach students tu du preparati\.e rractions safely and efficiently, who will? This is not a major prahlem in departments that require a third semester of advanced organic laboratory. The preparative techniques can he covered in the advanced course, with a smaller group of students under closer supervision. Many departments offer only two semesters of formal organic laboratory, however. These departments must supplement the microscale experiments with additional exercises that teach the missing preparariw rrchniquex. Any book showing this one's oqinality is likelv tu have somc rouehedees. " - In thivcasr. the poor quality of the equipment diagrams is a minor source of irritation. These computer-generated drawings lack the smoothness and the perspective of a r t i d s line drawings. Round-bottomed flasks look like Chinese lanterns, threaded joints Look like rows of caterpillars, and rubber bands and copper wires look like headed necklaces. An artist could easily make much clearer per-
spective drawings of these experimental setups. Although I douht that a student's organic laboratory experience should he exclusively microscale experiments, this hook has convinced me that any conceivable reaction can be taught effectively on the microscale. In an age of decreasing educational resources and increasing concern about disposing of used chemicals. Microscale Ormnie Laboratory clearly 'points the direction of the finture . -... .. The .... -Preface - .-- and the first five ehaoters on microscale techniques should be required reading for all of us who teach organic laboratories. ~
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Leroy G. Wade. Jr.
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Colorado State University Fwt Collins, CO 80523
Coordination Chemistry F. Basoio and R. C. Johnson. Science Re-
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views: Wilmington, DE, 1986. vl 143 pp. Figs. and tables. 15.5 X 23.3 cm.
$12.95. This second, revised and enlarged edition of a critically acclaimed, out-of-print book first published in 1964"has been updated to cover a host of interesting new areas in which the ideas of coordination chemistry have impact". Because 23 years have elapsed since t h e f i r s t e d i t i o n (See Kirschner, S. J. Chem. Educ. 1965.42, 291 for a review)-possibly a time interval worthy of the Guinness Book of World Records-a new generation of chemical educators and students needs to become acq u a i n t e d with t h i s s h o r t h u t classic monograph intended to present the basic principles of coordination chemistry in more detail than is customary in most general chemistry textbooks. Written for persons in chemistw. it with a limited backmound " can serve as e supplement to high arhi~olor infroductmy college chrniistry courses,as a aubjrrt fur a special rhernistryseminar,or aa an introduction or review for graduate students, health professionals, or others who plan to do work involving metal ions and complexes. The chapter titles give some idea of the scope of this volume: (1)"Introduction and Historical Development" (16 pp.); (2) "The Coordinate Bond" (28 pp.); (3)"Stereoehemistry" (18 pp., with a new section, "Complexes with Unusual Structural Features"); (4) "Preparations and,Reactions of Cwrdi(Continued on page A192)
Reviewed In This Issue Books
Reviewer
D. W. Mayo, R. M. Pike, and S. S. Butcher, Microscale Organic Laboratory F. Basoloand R. C. Johnson, Coordination Chemistry Mark Liffmannand Donald K. Yeomans, Comet Haiiey: Once in a Lifetime Continuing Series
Leroy G. Wade, Jr.
A101
George B. Kauffman George B. Kauffman
A191 A192 A195
Volume 84
Number 8
August 1987
A191
