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With this book, as stated in their preface, the authors intend to facilitate the integration of photochemical synthesis procedures into "experimental courses for students". Of this potentially broad audience, however, they want to augment the "training of chemists" in particular, thereby excluding most of the students in American colleges and universities who venture only as far as undergraduate organic chemistry laboratory courses. This limitation is appropriate, and it is underlined by examination of the projects in the book. I found about a dozen experiments suitable for an undergraduate lab course; even this small number significantly expands the existing repertoire of commonly used photochemical experiments. Many more contain features (e.g., 24-hour or longer reaction times, ozonolysis, $50 per person starting materials, high-vacuum distillation, rotary evaporation, multifraction column chromatography) which make them too lengthy, dangerous, expensive, and/or logistically and technically demanding to use in a course for 150 (or 20) sophomores. The remaining clientele consists of upper-level undergraduate chemistry majors and chemistry graduate students. For an advanced laboratory course containing no more than 15 such students, a round-robin experimental format is feasible, wherein only a few people at a time are using high-tech equipment such as vacuum systems, rotary evaporators, or photoreactors. Many of the experiments in this book could be programmed advantageously into such a course.
The book is very well organized, starting with some useful advice on pre-experiment preparation, an up-to-date compilation of textbooks, journals, and other publications on photochemistry, and a series of paragraphs on the significance of starting material purity, substrate electronic spectra, solvent choices, triplet/singlet excited state/sensitizer/quencher considerations, quantum yields and chemical yields, lamps/vessels/filters, and radiation/apparatus hazards.
The core of the book ranges through aldehydes/ketones, enones/dienones, N-containing chromophores, aromatics, alkenes/arylalkenes/cycloalkenes, organometallic compounds, photooxygenation/reduction, photochemistry in organized media, and photochromic compounds. Photochemical key steps are indexed both graphically and (a separate index) by experiment number with quick reference to lamp, filter, vessel/reactor, sensitizer (if any), and other specific conditions and comments. A third (subject) index appears to include all compounds and reactions (and types) used in the book.
Each major section (as listed above) begins with a helpful discussion of types of photochemical reactions undergone by that class of compounds, a brief preview (with contributor identification) of each project in the chapter, and recommended further reading. Each individual project consists of one or more steps, which include equations with excellent structural formulas, adequate to excellent experimental details (irradiation time sometimes is given only as "until disappearance of starting material"), excellent NMR/IR/UV/MS characterization of products, and original literature citations.
Editing could have been done more carefully. The authors (or translators) have structured many sentences awkwardly, in ways that sometimes make the intended meaning elusive (e.g., p 5, What is a "solvent fraction"?; p 204, "only frequently" probably should be "only rarely"). There are numerous misspellings, grammatical inconsistencies, and typos, not enough to detract from the effectiveness of the book, but enough to suggest that nobody gave the book a quick read-through (or a computer spell check) before publication. Some errors of substance came to my attention. On p 170, "delta G: free enthalpy" should be free energy. On p 171, B. Pandey's experiment (p 177) is described as involving an intramolecular cycloaddition reaction of an endo Diels-Alder adduct to give a cage compound; it is actually formation of an exo Diels-Alder adduct, and subsequent intramolecular cycloaddition would be impossible. On p 177, the dienophile and adduct molecular weights are two carbons short (readers are warned on p 1 to look for this kind of error). On p 288, the epoxide absolute configurations are incorrect (the diastereomers cannot have the same configuration at C-3), and incorrectly suggest that each diastereomer is a single enantiomer. On p 310, Figures 5a and 5b should be Figure 1 and (presumably) Figure 2.
I think that Photochemical Key Steps is a singularly compact, rich source of laboratory experiments which, with careful selection, could be used in laboratory courses at any level. I recommend it also as a supplement for a lecture course in photochemistry, organic synthesis, or organic reaction mechanisms. Finally, it can serve as an excellent source of problems for graduate-level cumulative examinations.
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