Intent and Purpose
Stereochemistry is the study of the static and dynamic aspects of the three-dimensional
shapes of molecules. It has long provided a foundation for understanding structure and reactivity.
At the same time, stereochemistry constitutes an intrinsically interesting research
field in itsownright.Manychemists find this area of study fascinating due simply to the aesthetic
beauty associated with chemical structures, and the intriguing ability to combine the
fields of geometry, topology, and chemistry in the study of three-dimensional shapes. In addition,
there are extremely important practical ramifications of stereochemistry. Nature is
inherently chiral because the building blocks of life (-amino acids, nucleotides, and sugars)
are chiral and appear in nature in enantiomerically pure forms. Hence, any substances created
by humankind to interact with or modify nature are interacting with a chiral environment.
This is an important issue for bioorganic chemists, and a practical issue for pharmaceutical
chemists. The Food and Drug Administration (FDA) now requires that drugs be
produced in enantiomerically pure forms, or that rigorous tests be performed to ensure that
both enantiomers are safe.
In addition, stereochemistry is highly relevant to unnatural systems. As we will describe
herein, the properties of synthetic polymers are extremely dependent upon the stereochemistry
of the repeating units. Finally, the study of stereochemistry can be used to probe
reaction mechanisms, andwewill explore the stereochemical outcome of reactions throughout
the chapters in parts II and III of this text. Hence, understanding stereochemistry is necessary
for most fields of chemistry, making this chapter one of paramount importance.