In recent years the choice of a given solvent for performing a reaction has become increasingly important. More and more, selective reagents are used for chemical transformations and the choice of the solvent may be determining for reaching high reaction rates and high selectivities. The toxicity and recycling considerations have also greatly influenced the nature of the solvents used for industrial reactions. Thus, the development of reactions in water is not only important on the laboratory scale but also for industrial applications. The p- formance of metal-catalyzed reactions in water for example has led to several new hydrogenation or hydroformylation procedures with important industrial applications. The various aspects of organic chemistry in water will be prese- ed in this book. Recently, novel reaction media such as perfluorinated solvents or supercritical carbon dioxide has proven to have unique advantages leading to more practical and more efficient reactions. Especially with perfluorinated solvents, new biphasic catalyses and novel approaches to perform organic reactions have been developed. These aspects will be examined in detail in this volume. Finally, the performance of reactions in the absence of solvents will show practical alternatives for many reactions. More than ever before, the choice of the solvent or the solvent system is ess- tial for realizing many chemical transformations with the highest efficiency. This book tries to cover the more recent and important new solvents or solvent systems for both academic and industrial applications.

More than a decade has passed since the appearance of the last edition of the book "Carbon Monoxide in Organic Synthesis." During the intervening period, the signi ficance of carbon monoxide chemistry has become even more evident. The oil crisis and the ever-present awareness of the constant depletion of the oil reserves have both contributed to a surge in activity. The fact that coal will once again replace oil in the near future as a feedstock source has been an impetus for new efforts in the field of carbon monoxide chemistry. Moreover, older almost neglected processes such as the Fischer-Tropsch synthesis have become a focal point for new activities. Therefore, the time was ripe to fundamentally revise "Carbon Monoxide in Organic Synthesis" and to complete its coverage by introducing the chapters "Homo logation" and "Carbon Monoxide Hydrogenation." However, other important sectors of carbon monoxide chemistry such as the con version of synthesis gas to methanol or higher alcohols were excluded. These are treated in the book "Chemierohstoffe aus Kohle," which devotes considerable attention to these syntheses. I would like to thank Drs. Bahrmann, Comils, Frohning, Mullen and Tummes, who had the task of compiling and critically evaluating the large volume of literature which has appeared during the last decade."