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This series deals with important issues in stereochemistry, which is the three-dimensional spatial orientation of molecules, also called the chirality (or handedness) of molecules. Topics in Stereochemistry, previously edited by "the father of stereochemistry" Ernest L. Eliel, is a longstanding, successful series covering the most important advances in the field. The much-anticipated Volume 26 on stereochemical aspects of organolithium compounds includes chapters on Asymmetric Deprotonations Using Chiral Lithium Amide Bases, Self-Regeneration of Stereocenters (SRS) via Stereolabile Axially Chiral Intermediates, and more.
The world is chiral. Most of the molecules in it are chiral, and
asymmetric synthesis is an important means by which enantiopure
chiral molecules may be obtained for study and sale. Using examples
from the literature of asymmetric synthesis (more than 1300
references), the aim of this book is to present a detailed analysis
of the factors that govern stereoselectivity in organic reactions.
It is important to note that the references were each individually
checked by the authors to verify relevance to the topics under
discussion. The study of stereoselectivity has evolved from issues of
diastereoselectivity, through auxiliary-based methods for the
synthesis of enantiomerically pure compounds (diastereoselectivity
followed by separation and auxiliary cleavage), to asymmetric
catalysis. In the latter instance, enantiomers (not diastereomers)
are the products, and highly selective reactions and modern
purification techniques allow preparation - in a single step - of
chiral substances in 99% ee for many reaction types. After an explanation of the basic physical-organic principles of
stereoselectivity, the authors provide a detailed, annotated
glossary of stereochemical terms. A chapter on "Analytical Methods"
provides a critical overview of the most common methods for
analysis of stereoisomers. The authors then follow the 'tried-and-true' format of grouping
the material by reaction type. Thus, there are four chapters on
carbon-carbon bond forming reactions (enolate alkylations,
organometal additions to carbonyls, aldol and Michael reactions,
and cycloadditions and rearrangements), one chapter on reductions
and hydroborations (carbon-hydrogen bond forming reactions), and
oneon oxidations (carbon-oxygen and carbon-nitrogen bond forming
reactions). Leading references are provided to natural product
synthesis that have been accomplished using a given reaction as a
key step. In addition to tables of examples that show high selectivity, a transition state analysis is presented to explain - to the current level of understanding - the stereoselectivity of each reaction. In one case (Cram's rule) the evolution of the current theory is detailed from its first tentative (1952) postulate to the current Felkin-Anh-Heathcock formalism. For other reactions, only the currently accepted rationale is presented. Examination of these rationales also exposes the weaknesses of current theories, in that they cannot always explain the experimental observations. These shortcomings provide a challenge for future mechanistic investigations.
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