A Green Chemistry Approach to Asymmetric Catalysis:  Solvent-Free and Highly Concentrated Reactions

Abstract

In 1999, he moved to his current position at the University of Pennsylvania where he was promoted to associate professor in 2002 and professor in 2005. Walsh has received several awards, most recent of which was the 2006 Philadelphia Section Award of the ACS. Walsh's interests are in asymmetric reactions, development of new methods, reaction mechanisms, and inorganic chemistry. Hongmei Li received her B.Sc. in chemistry at the Dalian University of Technology in 1999 and her M.Sc. degree in inorganic chemistry (2002) at the Peking University with Professor Jianhua Lin. She began her Ph.D. at the University of Pennsylvania under the direction of Professor Patrick J. Walsh in 2002, during which she worked on the catalytic asymmetric addition of organozinc reagents to ketones and application of bimetallic intermediates in organic synthesis.

Mechanochemistry: opportunities for new and cleaner synthesis

“…Firstly, it is increasingly clear that is effective, and even advantageous, in ever-widening types of synthesis. Secondly, our current dependence on solvents appears increasingly unsustainable [1] since it is wasteful of fossil-derived materials (e.g. 85% of chemicals used in the pharmaceutical industry are solvents and even if recycled typical recovery rates are only 50-80% [1b] ), environmentally problematic, hazardous and energy-demanding with regard to solvent production, purification and recycling.…”

Ferrocene-derived P,N ligands: synthesis and application in enantioselective catalysis

“…Enantioselective catalysis can be considered as "Green" since it allows the introduction of a chiral stereocenter in large amounts of prochiral substrates, by utilizing only a limited amount of valuable catalyst [18,19]. As such, classical stoichiometric methodologies which create a lot of waste are circumvented, e.g., the use of chiral auxiliaries or the separation of two enantiomers via a resolution step.…”

Iodine-catalyzed Transformation of Aryl-substituted Alcohols Under Solvent-free and Highly Concentrated Reaction Conditions

“…[1][2][3] Transformations of neat reactants under solvent-free reaction conditions (SFRC) are one of the best solutions in this regard. [4][5][6][7] In the solid/solid system, a remarkable reaction rate enhancement was observed just by introducing small amounts of solvent vapor into the reaction mixture. 8 Moreover, the course of the reaction can be dramatically influenced under highly concentrated reaction conditions (HCRC).…”