Project

Discipline

catalysis; aqueous interfaces; organic synthesis; molecular dynamics; electronic structure; molecular systems

Lead
Lay summary
p, li { white-space: pre-wrap; } In nature aqueous surfaces and interfaces are ubiquitous and are involved in a wide variety of biological processes. It is therefore remarkable that, up until recently, organic synthesis in laboratory has mainly neglected water. This situation has been rapidly changing ever since Sharpless and co-workers demonstrated that many classes of organic transformations exhibit increased reaction rates, enhanced selectivity and improved yields when performed in heterogeneous water emulsions. A thorough understanding of the role that aqueous interfaces play in the catalytic phenomenon described by Sharpless and others is crucial for designing effective laboratory and industrial-scale synthetic processes. However, obtaining detailed information about molecular-scale transformations at these interfaces interfaces represents a formidable challenge. Experimental investigation of complex dynamics of chemical species at liquid-liquid interfaces today is expensive, technically difficult, and often produces results without a clear interpretation. At the same time, computer simulations are either insufficiently accurate or so computationally demanding that studying interfacial processes is unfeasible. For these reasons, our knowledge of the mechanism of reactions in water emulsions is fragmentary and the origin of the catalytic effect at aqueous interfaces remains unclear. The main aim of this research project is studying the microscopic origins of the enhanced reactivity phenomenon observed in heterogeneous water emulsions. To achieve this goal, the principal investigator will develop and apply efficient and accurate methods for molecular dynamics simulations specifically tailored to take advantage of aspects of the electronic structure that are characteristic of molecular systems. The proposed research will provide well-founded input for a rational design of synthetic processes that can more effectively utilize the catalytic properties of aqueous interfaces. Furthermore, the developed computational algorithms will make completely new phenomena accessible in computer simulations. They can be immediately applied to study physico-chemical processes in molecular systems such as environmentally important chemical transformations at water surfaces in the atmosphere, the transport of ions and molecules across interfaces in phase-transfer catalysis and phase transitions in ionic liquids and liquid crystals. The theoretical advances in this work will also provide a mathematical foundation for the development of more sophisticated methods for computer simulations of solvation, association-dissociation, self-assembly and many other condensed phase phenomena in complex molecular systems of chemical, biochemical and nanotechnological interest.

Direct link to Lay Summary

Last update: 21.02.2013

Active participation

Self-organised

Communication	Title	Media	Place	Year

In nature aqueous surfaces and interfaces are ubiquitous and are involved in a wide variety of biological synthetic pathways. It is therefore remarkable that, up until recently, in vitro organic synthesis has mainly neglected water. This situation has been rapidly changing ever since Sharpless and co-workers demonstrated that many classes of organic transformations exhibit increased reaction rates, enhanced selectivity and improved yields when performed in heterogeneous water emulsions.A thorough understanding of the role that aqueous interfaces play in the catalytic phenomenon described by Sharpless et al. is crucial for designing effective laboratory and industrial-scale synthetic processes. However, obtaining detailed information about molecular-scale transformations at these interfaces interfaces represents a formidable challenge. Experimental investigation of complex dynamics of chemical species at liquid-liquid interfaces today is expensive, technically difficult, and often produces results without a clear interpretation. At the same time, computer simulations are either insufficiently accurate or so computationally demanding that studying interfacial processes on appropriate time and length scales is unfeasible. For these reasons, our knowledge of the mechanism of reactions in water emulsions is fragmentary and the origin of the catalytic effect at aqueous interfaces remains unclear.I propose a collaboration with Professor Kuhne at the University of Mainz in Germany with the goal of studying the microscopic origins of the enhanced reactivity phenomenon observed in heterogeneous water emulsions. To this end, I will develop and apply efficient and accurate methods for first-principle molecular dynamics simulations specifically tailored to take advantage of aspects of the electronic structure that are characteristic of molecular systems.The proposed research will provide well-founded input for a rational design of synthetic processes that can more effectively utilize the catalytic properties of aqueous interfaces. Furthermore, the developed computational algorithms will make completely new phenomena accessible in computer simulations. They can be immediately applied to study physico-chemical processes in molecular systems such as environmentally important chemical transformations at water surfaces in the atmosphere, the transport of ions and molecules across interfaces in phase-transfer catalysis and phase transitions in ionic liquids and liquid crystals. The theoretical advances in this work will also provide a mathematical foundation for the development of more sophisticated methods for computer simulations of solvation, association-dissociation, self-assembly and many other condensed phase phenomena in complex molecular systems of chemical, biochemical and nanotechnological interest.