Project description
One of the key features of life is the presence of its essential molecules such as amino acids, proteins, sugars and DNA as one mirror image form. These single handed chiral (from Greek χειρ (kheir), “hand”) structures are considered crucial for the evolution of life on the earth; a phenomenon called homochirality. The presence of exclusive single mirror image forms is often denoted as “A Signature of Life “. Homochirality is essential for e.g. molecular recognition and information processing, enzyme functioning and cell replication. However, the origin of biomolecular homochirality is one of our great mysteries.
One of the major questions in bio-chemical evolution is “How to break the symmetry? Two key aspects will be targeted: i) Chiral symmetry breaking; ii) Chiral amplification. What is the mechanism to create a symmetry breaking at the molecular level? How to create a tiny chiral bias i.e. preference for one handedness prebiotic relevant molecules? How to achieve chiral amplification to arrive at exclusive homochiral molecules? In this PhD project we aim use model reactions to discover prebiotic relevant systems for chiral enrichment.
Photochemistry with circular polarized light will be studied on model compounds to either accomplish i) deracemization or ii) absolute asymmetric synthesis. Circular polarized light (CPL, the light used for irradiation has either left-or right- handedness) is considered highly relevant from a prebiotic perspective (strong exposure of molecules to intense irradiation and abundantly present in outer space). Alternatively, the use of magnetic fields in radical coupling reactions offers an exciting opportunity to create a small chiral bias taking advantage of the recently discovered CISS effect leading to chiral spin control chemical radicals. Towards chiral amplification our novel approach is based on phosphorylation of amines and amino acids to study chiral auto-selection and enrichment of chirality. The introduction of phosphorus moieties in molecules is highly relevant from prebiotic perspective. We recently discovered that phosphorylation of amino acids can induce aggregation and provides a novel selection mechanism to amplify tiny chirality in water. Absolute asymmetric synthesis: The origin, control, and amplification of chirality; B. L. Feringa and R. A. van Delden, Angew. Chem. Int. Ed. 1999, 38, 3419-3438 Chiral Amplification of Phosphoramidates of Amines and Amino Acids in Water; V. Dašková, J. Buter], A. K. Schoonen, M. Lutz, F. de Vries, B. L. Feringa, Angew. Chem. Int. Ed. 2021, 60, 11120-11126
Additional specifications
We look for a candidate with a MSc in chemistry preferrably wit expertise in synthesis, stereochemistry or supramolecular chemistry.
