Role in environmentally benign synthesis

Aluminum phosphate based molecular sieves, role in environmentally benign synthesis of chemicals, 128 Amines, organic isocyanate generation, 49-57... 

Catalysis will play a vital role in the 21 century in the environmentally benign synthesis of new and existing chemicals. These processes will be designed with an emphasize on both environmental and economic factors. This chapter describes the types of catalysts currently used in the syntheses of bulk and fine chemicals and identifies those most likely to have a beneficial impact, economically as well as environmentally, for chemical manufacturing in the future. 

In 2007, Milstein reported an approach for the transition metal catalysed intermolecular formation of amides from alcohols and amines in the absence of a hydrogen acceptor (Scheme 12.19). In contrast with conventional amide synthesis from activated carboxylic acid derivatives which produces chemical waste, this environmentally benign approach produces hydrogen gas as the only byproduct. The catalyst used for this reaction is a dearomatised Ru(PNN)pincer complex which serves as a bifunctional catalyst. The ligands, as well as the metal centre, play a role in bond making or bond breaking steps of the catalytic cycle. 

---