Denmark S.E., Siegel J.S. Topics in Stereochemistry. Volume 25

John Wiley & Sons, Inc., 2006. — 424 p.Shape and symmetry strongly infl uence the reactivity of a molecule. The state-of-the-art methods for determining molecular structure make it easy to elucidate the stereochemistry of molecules. Various physical methods such as vibrational and microwave spectroscopy, and X-ray or electron diffraction analysis, are mature analytical methods. Among these methods, automated structural studies of molecules in crystals by X-ray analysis is the most powerful method for analyzing stereochemistry. The stereochemistry elucidated in the crystal provides a basis for interpreting chemical reactions and properties of compounds, in the solid state and in solution. Although differences may arise between solid and solution, the quantitative geometric data obtained for molecules in crystals can often help us explain those differences as well.
It is well established that solid state reactions can be exploited as useful synthetic methods. The stereochemistry of molecules in crystals provides the basis to rationalize the steric course and mechanism of solid state reactions. In some cases, the stereochemistry of molecules can be controlled by formation of an inclusion crystal with a host compound. In the inclusion crystal, molecules are ordered enabling the reaction to proceed through a stereospecifi c course. In other cases, one tautomer can be isolated in a pure state from an equilibrium mixture by formation of an inclusion crystal with a host, and the stereochemistry of the tautomer can be studied by X-ray crystallographic analysis. Study of the stereochemistry of molecules in crystals is also advantageous in clarifying the intermolecular and intramolecular interactions, which are important factors controlling molecular shape and molecular arrangement in the crystal. Furthermore, from data obtained during the stereochemical study of molecules in crystals, new crystals and inclusion crystals that are useful as new materials and are applicable to stereoselective reactions can be designed.
The study of the stereochemistry of molecules in crystals is important for the lofty goal of crystal engineering. If chemists are ever going to achieve this, it will fi rst be necessary to have a far greater and more refi ned understanding of the structure-property principles encoded in the stereochemistry of crystals.
The chapters of this volume are written by academic scientists who are actively engaged in research in this fi eld. The topics cover a multitude of themes. In the fi rst chapter, I review the progress made in inclusion crystals on the stereochemistry of molecules. Professor Ogawa reveals the extent to which one must go to truly understand the conformational effects in crystal structure determination.
Professors Goldberg and Nangia regale us on the fascinating network structures that arise from cooperative supramolecular interactions in crystals. The importance of supramolecular effects is further expanded by Professor Nishio on CH-pi-interactions and Professor Kato on structure-property effects induced by intermolecular interactions in crystalline platinum complexes. Beautiful examples of controlled molecular reactivity in crystals, a type of crystal engineering, are found in chapters by Professors Kaupp and Garcia-Garibay. Professor Harada discusses the design of powerful chiral auxiliaries for enantiomeric resolution and the determination of absolute confi guration. Hetero and Homochirality in crystals is critically reviewed by Professors Levkin, Torbeeve, Lenev, and Kostaynovsky.
It has been a pleasure working with these authors to create this volume of Topics in Stereochemistry. As guest editor, I hope this book will be useful for chemists who are interested in the stereochemistry of molecules, solid state chemistry and crystal engineering.