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Dead Ends and Detours. Direct Ways to Successful Total Synthesis. By Miguel A. Sierra and Mara C. de la Torre

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dations, and the role of different reaction media in transition-metal-catalyzed
reactions. It begins in Chapter 1 with
five excellent reviews on homogeneous
and heterogeneous hydrogenation, by
Noyori (Nobel Prize laureate, 2001)
and other outstanding authors.
The articles in Chapter 2 of this
volume deal in depth with catalytic oxidations, beginning with a short overview
by Sheldon and Arends of the basics of
oxidation reactions, which emphasizes
the recent progress achieved in oxidation catalysis by describing selected
examples, including catalytic enantioselective oxidations. The chapters on
“Asymmetric Dihydroxylation” and
“Asymmetric Aminohydroxylation” by
Sharpless (one of the 2001 Nobel Prize
laureates in chemistry) and co-authors
give a comprehensive overview of asymmetric conversion of olefins into synthetically very useful diols and aminoalcohols.
The articles in Chapter 3 review
exciting new topics such as transitionmetal catalysis using ionic liquids, catalysis in the liquid phase under high pressure, applications of microwave radiation
and ultrasound for organic synthesis, and
photocatalysis using transition metals.
Thus, the book covers a very broad
range of reactions and describes the
application of transition metals for
organic synthesis and fine chemicals
production, offering readers a concise
and highly informative treatment of
important selected aspects.
This book can be recommended for
all scientists working in the area of catalysis, whether in industrial research and
development or in universities. The
book is less suited as a textbook for
undergraduate students, since not all
the mechanistic concepts are explained
in enough detail to provide sufficient
insights for the less-well-informed
reader. However, it should be of great
interest to students in advanced courses
and to postdoctoral researchers who
have commenced working in this field.
Svetlana B. Tsogoeva
Institut fr Organische und
Biomolekulare Chemie
Universitt Gttingen (Germany)
3338
Dead Ends and Detours
Direct Ways to
Successful Total
Synthesis. By
Miguel A. Sierra and
Mara C. de la Torre.
Wiley-VCH, Weinheim 2004.
276 pp., softcover
$ 79.95.—ISBN
3-527-30644-7
The excitement of journeys in total synthesis stems from their unpredictability;
this sentiment is perhaps best encapsulated by some thoughts penned by Professor Albert Eschenmoser: “The complexity in the behavior of organic molecules is such that the first execution of
any chemical synthesis based on a
design is always a venture into the
uncertain, an experiment run to find
out whether and under what conditions
the elements of design do indeed correspond to reality.” Despite recent advances, practitioners of synthesis are still
humbled by the unpredictable reactivity
of complex molecules. The fact that
endeavors in total synthesis seldom
transpire as planned is perhaps not
advertised enough. Accordingly, it is
especially gratifying to find this subject
expounded upon in great detail by
Sierra and de la Torre in their new text.
Dead Ends and Detours provides the
reader with a well-organized glimpse
into some of the trials and tribulations
encountered in approximately 35 magnificent total syntheses. The format and
content is very similar to a review published a few years ago by the same
authors (Angew. Chem. Int. Ed. 2000,
39, 1538–1559); it contains 15 syntheses
in addition to those presented originally
(also those from the review are dramatically expanded here). Over the course
of eight chapters, in which the examples
are grouped according to the type of
unexpected hurdle encountered, the
authors describe measures by which
they were overcome. These range from
small changes of strategy (such as the
fine-tuning of reaction conditions) to
complete strategic overhauls that were
necessitated by having relied on misleading model systems or by the inexplicable reactive behavior of a common
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.angewandte.org
functional group. In several instances,
the authors actually carried out computational studies (MM2) to determine
the root of the problem. The computed
result was often in line with that which
was expected rather than that which
was actually observed, which attests to
the empirical reality of synthetic work.
The hurdles faced are often astonishing,
such as the case of an olefin that refused,
for no apparent reason, to be hydrogenated (octalactin, Chapter 4), or an
equally mysterious case of two atropisomers that differed dramatically in
reactivity (damavaricin D, Chapter 3).
Several cases are also presented where,
in hindsight, there is a rationale for the
cause of the failure, yet those reasons
did not seem compelling enough to
rule out a particular approach at the
start. For example, a major change of
plans in a beautiful synthesis of milbemycin (Chapter 5) was prompted by
the detrimental elimination of a sulfoxide group (after an unforeseen epimerization event) instead of the elegant [2,3]
rearrangement that was expected.
Each chapter presents a number of
syntheses (from three to seven), and
describes the key steps in each case.
The discussion of each molecule is
organized into sections: target relevance, synthetic plan, predictable problems, actual synthesis, and evaluation.
This logical format allows the reader to
rapidly ascertain the essence of each
synthetic endeavor and the problems
encountered therein. For the benefit of
new students, key synthetic methods
and concepts are often highlighted in
boxes at the end of each synthesis.
From a more critical viewpoint, the
book contains several spelling, grammatical, and typographical errors, but
is nevertheless well-written and free of
any major factual errors that would misinform readers. One might consider the
subtitle of the book as misleading,
since the book offers no clues on
“direct ways to successful total synthesis.” Indeed, it is the dead ends, detours,
and serendipitous discoveries (the “indirectness”) associated with synthesis that
fuel much of its charm, appeal, and vitality. To be sure, when embarking on the
synthesis of a new structural type, one
must often rely on intuition, since
there are no generally valid “direct
ways.” As Professor Samuel DanishefAngew. Chem. Int. Ed. 2005, 44, 3337 – 3339
Angewandte
Chemie
sky recently remarked: “Given the episodic nature of our science, wisdom
may well be more valuable than cleverness.” In any case, by the end of this
book, the reader will certainly have
gained much wisdom and learned valuable lessons from the surprises encountered by others. Since the target audience of this book will likely own Nicolaous “Classics in Total Synthesis”
series, the authors have wisely ensured
Angew. Chem. Int. Ed. 2005, 44, 3337 – 3339
that there is no overlap in the syntheses
discussed (with the exception of a brief
mention of brevetoxin B in Chapter 1),
thus giving it unique didactic value.
In conclusion, this book is akin to a
compilation of riveting nonfiction short
stories for chemists. It can be used as
an excellent supplementary text for a
class in advanced organic synthesis, or
as an enjoyable Sunday afternoon read
www.angewandte.org
for practitioners of synthesis at any
level.
Phil S. Baran
Department of Chemistry
The Scripps Research Institute
La Jolla, California (USA)
DOI: 10.1002/anie.200485273
2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
3339
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