Catalysis is a fundamentally sustainable process which can be used to produce a wide range of chemicals and their intermediates. Focussing on those catalytic processes which offer the most sustainability, this two-part book explores recent developments in this field, as well as examining future challenges. Focussing on catalysis without metals or other endangered elements, each chapter covers a different type of organocatalyst. Beginning with chapters on acid and base catalysis, the book then concentrates on asymmetric catalysis. Several chapters cover pyrrolidine-based and cinchona alkaloid-based catalysts, whilst other chapters examine further organoctalysts which are constructed only from sustainable elements. Together with "Sustainable Catalysis: With Non-endangered Metals", these books examine the progress in sustainable catalysis in all areas of chemistry, and are an important reference for researchers working in catalysis and green chemistry. "This book set is highly recommended for the researchers involved in sustainability projects. The book set is an excellent overview of the field and makes an important emphasis on catalysis with different metals as an area of growing interest" - Angewandte Chemie Catalysis is a fundamentally sustainable process which can be used to produce a wide range of chemicals and their intermediates. Focussing on those catalytic processes which offer the most sustainability, this two-part book explores recent developments in this field, as well as examining future challenges. Focussing on catalysis without metals or other endangered elements, each chapter covers a different type of organocatalyst. Beginning with chapters on acid and base catalysis, the book then concentrates on asymmetric catalysis. Several chapters cover pyrrolidine-based and cinchona alkaloid-based catalysts, whilst other chapters examine further organoctalysts which are constructed only from sustainable elements. Together with Sustainable Catalysis: With Non-endangered Metals , these books examine the progress in sustainable catalysis in all areas of chemistry, and are an important reference for researchers working in catalysis and green chemistry. Professor North is Chair of Green Chemistry at the University of York and is joint chair of the EPSRC-supported CO2Chem Grand Challenge Network. His research interests are mostly in the area of green organic chemistry, especially sustainable catalysis and the utilization of sustainable feedstocks including CO2. He has published more than 190 papers and holds six patents. Sustainable Catalysis Without Metals or Other Endangered Elements Part 1 By Michael North The Royal Society of Chemistry Copyright © 2016 The Royal Society of Chemistry All rights reserved. ISBN: 978-1-78262-640-4 CHAPTER 1 Introduction MICHAEL NORTH 1.1 Introduction Sustainable Catalysis: With Non-endangered Metals, Parts 1 and 2 were concerned with catalysis brought about with the aid of Earth crust abundant metals as represented by those coloured green or orange in Figure 1.1. However, a number of nonmetals are also relatively abundant in the Earth's crust, biosphere or atmosphere and these include hydrogen, carbon, nitrogen, oxygen, silicon, sulfur and chlorine. Therefore, Sustainable Catalysis: Without Metals or Other Endangered Elements, Parts 1 and 2 will focus on catalysts comprised of these elements that function without the need for any metal. The focus of Sustainable Catalysis: Without Metals or Other Endangered Elements is largely on a topic that has become known as "organocatalysis", i.e. catalysis by organic molecules and in particular, asymmetric catalysis by organic molecules. However, the scope is broader than that as, for example, protons are widely used to catalyse many chemical reactions, such as ester hydrolysis (Scheme 1.1). Thus, the next three chapters of this volume provide an overview of acid and base catalysis, before the subsequent 20 chapters of these two volumes cover asymmetric organocatalysis by various classes of organocatalyst. These latter chapters will focus predominantly on relatively recent work and may give the impression that asymmetric organocatalysis is a new topic. The term organocatalysis was certainly only coined in the 1990s, but the use of metal-free catalysts has a history dating back over 100 years. Therefore, the remainder of this introductory chapter will provide a historical perspective to asymmetric organocatalysis. Enzymatic catalysis has not been included within this work as the focus is on synthetic catalysts derived from abundant elements. However, many enzymes function without the need for a metal (abundant or otherwise) within their active site and hence could be classified as organocatalysts. 1.2 Historical Perspective Asymmetric organocatalysis can be traced back over one hundred years and early work was largely concerned with catalysis of a single reaction: the asymmetric addition of hydrogen cyanide to