P h ysica I organic chemistry

mechanisms of both chemical and enzymatic reactions in solution, the invention of molecular me-chanics and of photoaffinity labeling, and the application of pseudorotation to phosphate ester chem-istry. In 1964-65 he chaired the National Academy of Sciences ’ survey of chemistry (“Chemistry: Opportunities and Needs”, National Academy of Sciences Press, 1965). He has received a number of awards in chemistry here and abroad, including a National Medal of Science, and has been elected to membership in several honorary societies. Physical organic chemistry was originally devoted to an understanding of the structures of compounds and the mechanisms of reactions in organic chemistry (1). It was marvelously successful, and not merely accom-panied but fundamentally caused a revolution in synthesis. Today, the methods and ideas of physical organic chemistry can be applied more broadly, and in particular to enzymology, and other areas of bio-organic chemistry. Prior to the elucidation of reaction mechanisms, successful synthesis depended on a vast knowledge of the chemical literature. Various past syntheses, mostly developed by intensive empirical experimentation, were reported, and anyone planning new work could and did draw extensively on the record of the past. So suc-cessful was this methodology that, fifty years ago, most practitioners refused to acknowledge the importanc