ABSTRACT
References .......................................................................................................................... 586
Organic synthesis is a central theme in many disciplines of science ranging from chemistry
through biology to materials. Over the last one and half centuries, organic synthesis has
evolved to such a degree of sophistication that it allows molecules of almost any complexity to
be constructed. However, traditional synthetic methodologies are dominated by stoichiomet-
ric reactions, multistep manipulation, and use of hazardous reagents, and as such, they are
raw material and energy intensive and generate large amounts of waste. Some of the well-
known examples in this regard include the use of stoichiometric metals, metal hydrides, and
metal oxides, e.g., Zn, Na, LiAlH4, NaBH4, K2Cr2O7, and KMnO4, for reduction and
oxidation, and the use of stoichiometric metal reagents, e.g., AlCl3 and RMgX, for the
formation of CC bonds. A clear indication of the impact of organic synthesis on the environment is seen in Sheldon’s E factor, which suggests that the pharmaceutical industry,
a domain of synthetic organic chemistry, generates 25 to >100 kg waste for every kg of the product [1]. The key to dealing with these problems is to use catalysts.
