The effects of heat and light on chemical reactions have long been known and un derstood. Ultrasound has been known to promote chemical reactions for the past 60 years, but despite this, it did not attract the attention of synthetic chemists until recently. This arose historically from early studies which concentrated almost exclu sively on reactions in aqueous media and was also, in some measure, due to the availability of suitable technology. Since the early 1980s a plethora of literature has appeared of direct interest to synthetic chemists and the field has been developing rapidly. The aim of this book is to bring the background of this fascinating field to the atten tion of a wider audience. It explores the literature to date and attempts to indicate other areas in which ultrasound may be exploited. It also hopes to explode some of the myths surrounding this area which have hitherto been regarded by the synthetic community as a bit of a black art! Existing books and reviews have tended to concentrate on the physics of sonochem istry and to catalogue the instances in which ultrasound has proved useful in tack ling synthetic problems. Our aim has been to stress the relevance of this technique to synthetic chemists and we have included a section which deals with the practical aspects of carrying out these reactions.

The series Topics in Current Chemistry Collections presents critical reviews from the journal Topics in Current Chemistry organized in topical volumes. The scope of coverage is all areas of chemical science including the interfaces with related disciplines such as biology, medicine and materials science. The goal of each thematic volume is to give the non-specialist reader, whether in academia or industry, a comprehensive insight into an area where new research is emerging which is of interest to a larger scientific audience. Each review within the volume critically surveys one aspect of that topic and places it within the context of the volume as a whole. The most significant developments of the last 5 to 10 years are presented using selected examples to illustrate the principles discussed. The coverage is not intended to be an exhaustive summary of the field or include large quantities of data, but should rather be conceptual, concentrating on the methodological thinking that will allow the non-specialist reader to understand the information presented. Contributions also offer an outlook on potential future developments in the field.

Total Synthesis of Bioactive Natural Products provides step-by-step guidelines for effectively synthesizing the most promising bioactive agents from a broad range of natural products. Beginning with a concise background that outlines the benefits and challenges faced in effective synthesis, the book goes on to provide individual outlines for approximately 100 of the most promising bioactive agents. Taking a logical, user-friendly approach, the systematic name, compound class, structure, natural source, pharmaceutical potential and synthetic routes for each structure are detailed, with clear illustrations throughout, making this book an essential and practical guide for anyone working with both synthesis and natural products. - Provides individual outlines for the total synthesis of approximately 100 bioactive natural molecules - Outlines each step of the process in detail, with full experimental information supported by extensive schemes - Includes retrosynthetic analyses, reaction sequences and stereochemically crucial steps for each molecule

Organic chemistry has played a vital role in the development of diverse molecules which are used in medicines, agrochemicals and polymers. Most ofthe chemicals are produced on an industrial scale. The industrial houses adopt a synthesis for a particular molecule which should be cost-effective. No attention is paid to avoid the release of harmful chemicals in the atmosphere, land and sea. During the past decade special emphasis has been made towards green synthesis which circumvents the above problems. Prof. V. K. Ahluwalia and Dr. M. Kidwai have made a sincere effort in this direction. This book discusses the basic principles of green chemistry incorporating the use of green reagents, green catalysts, phase transfer catalysis, green synthesis using microwaves, ultrasound and biocatalysis in detail. Special emphasis is given to liquid phase reactions and organic synthesis in the solid phase. I must congratulate both the authors for their pioneering efforts to write this book. Careful selection of various topics in the book will serve the rightful purpose for the chemistry community and the industrial houses at all levels. PROF. JAVED IQBAL, PhD, FNA Distinguished Research Scientist & Head Discovery Research Dr. Reddy's Laboratories Ltd.

Traditionally heat and light are thought as energy sources to drive a particular chemical reaction, but now ultrasound is a promising energy source for this purpose. The collapse of a bubble generates a wide range of high temperatures and pressures, and therefore, use of ultrasound has a considerable potential in chemical and allied sciences. Ultrasound-assisted reactions are green and economically viable alternatives to conventional techniques. This new volume presents a complete picture of ultrasound-assisted reactions and technologies that can be used in organic synthesis, polymer synthesis and degradation, nanomaterials, wastewater treatment, food ingredients and products, pharmaceutical applications, bioenergy applications, and more. This volume aims to shed light on the diversified applications of ultrasound and its significant role as a green chemical pathway. Sonochemistry deals with the effect of ultrasonic waves on chemical systems. It has green value because of non-hazardous acoustic radiation and is therefore duly recognized as a green chemistry by synthetic chemists as well as environmentalists. There is no direct interaction of ultrasound with molecular species, but the observed chemical and physical effects of ultrasound are due to the cavitational collapse, which produces drastic conditions of temperature and pressure locally. It induces the formation of various chemical species, which cannot be easily attained under conventional conditions. Sometimes, these species are responsible for driving towards an unusual reactivity in molecular entities. This book, Sonochemistry: An Emerging Green Technology, provides the complete development of sonochemistry, starting with an introduction and basic concepts of sonochemistry and proceeding on to different types of sonochemical reactions, instrumentation, use of ultrasound in driving particular chemical reactions, and its applications in various fields, such as polymer synthesis, decontamination of water and wastewater, preparation of nanomaterials, food technology, pharmaceutical sciences, etc. The book also briefly discusses some areas that utilize ultrasounds of different frequencies. These include food products and their processing; anaerobic digestion of waste; and medical applications such as ultrasonography, sonodynamic therapy, drug delivery, etc. Sonochemistry will be successfully used on an industrial scale in pharmaceutical drugs, polymers, nanomaterials, food technology, material science, biogas production, etc. in years to come and will be an established green chemical technology of the future.

Ultrasonic irradiation and the associated sonochemical and sonophysical effects are complementary techniques for driving more efficient chemical reactions and yields. Sonochemistry-the chemical effects and applications of ultrasonic waves-and sustainable (green) chemistry both aim to use less hazardous chemicals and solvents, reduce energy consumpt

Green Sustainable Process for Chemical and Environmental Engineering and Science: Switchable Solvents explores the preparation, properties, chemical processes and applications of this class of green solvents. The book provides an in-depth overview on the area of switchable solvents in various industrial applications, focusing on the purification and extraction of chemical compounds utilizing green chemistry protocols that include liquid-liquid, solid-liquid, liquid-gas and lipids separation technologies. In addition, it includes recent advances in greener extraction and separation processes. This book will be an invaluable guide to students, professors, scientists and R&D industrial specialists working in the field of sustainable chemistry, organic, analytical, chemical engineering, environmental and pharmaceutical sciences. - Provides a broad overview of switchable solvents in sustainable chemical processes - Compares the use of switchable solvents as greener solvents over conventional solvents - Outlines eco-friendly organic synthesis and chemical processes using switchable solvents - Lists various industrial separations/extraction processes using switchable solvents

Power ultrasound has been used for many years in two specific industrial areas: cleaning and plastic welding. Over the last ten years an increasing interest has been shown in its potential for use over a much wider range of chemistry and processing which has been grouped together under the general title of sonochemistry. Most of these uses depend on the generation of acoustic cavitation in liquid media but this text, while underlining the importance of the physics and mathematics of cavitation, mainly concentrates on applications of the technology. After an introduction to the topic and some historical background to the uses of power ultrasound the general principles of acoustic cavitation are explored including some background physics, bubble dynamics and factors which influence cavitation. The remainder of the book incorporates a series of applications of sonochemistry which illustrate the types of physical and chemical effects of ultrasonically induced cavitation which will interest chemists and engineers alike. Amongst the major topics included are chemical synthesis, environmental protection and remediation of water, sewage and soils, polymer synthesis and processing, electrochemistry including both analytical and synthetic aspects and plating. The final chapter reviews the range of ultrasonic equipment available in the laboratory and the progress made towards the scale-up of sonochemistry. The level is introductory to semi-advanced and no topic has been taken to a particularly specialist level since it is intended that this should be of general interest to readers with a scientific background.

TEAN-LOUIS LUCHE A French poet of this eentury, Pierre Mae Orlan, wrote "Adventure does not exist, it is only in the mind of he who is pursuing it, and, as soon as it is at one's finger tips, it vanishes to come back to life, far away, in a different shape, at the frontiers of imagination". This sentence could be used to define the adventure that many sonochemists experienced. Most of them did not even suspect that the "laboratory trick" they were using was the first contact with a considerable amount of science. If a personal note is allowed here, it ean be interesting to mention the part played by chance in my involvement in sonochemistry. Almost 20 years ago, we had to perform an apparently simple Grignard reaetion with n-butylmagnesium bromide and geranial, but the results were repeatedly unsatisfactory. The one-pot Barbier technique was attempted, also without success. From my studies at the University, I imagined that the failure of the latter reaction could be caused by a common phenomenon known by solid state chemists as passivation, which in some cases can be overcome by ultrasonication. By chance, an ultrasonie bath was sitting on the next beneh, borrowed to clean some equipment. We clamped our reluctant reaction mixture into the bath, the reaction proceeded vigorously, and ... the adventure started. Without knowing anything about cavitation, high energies, ete., we had an illustration of Goethe's word "Am Anfang war die Tat" (at the Beginning was the Act).