Project description
Investigating organic chemical reactions at low temperatures
Reactions have physicochemical barriers that impede their progress. Catalysts are ubiquitously used to overcome many of these. Heat is also often applied to speed up reactions thanks to the increased motion of particles and their increasing number of collisions. In the far reaches of space and extreme cold, organic molecules are formed without this assistance. One theory is that a combination of quantum-mechanical tunnelling (QMT) and novel reactions with exceptionally low barriers could be the key. The EU-funded COLDOC project is evaluating this hypothesis through investigations that will reveal how QMT controls chemical reactivity and selectivity. This will be complemented by organic synthesis under cryogenic conditions for select compounds of interest.
Objective
This proposal ventures into organic chemical reactions under not-so-common conditions, namely in the cold, at insufficient energies, and under the action of hard radiation. As many organic molecules have been discovered in space or brought to earth in meteorites, they must have formed under such conditions through hitherto largely undisclosed mechanisms. One key hypothesis is that quantum-mechanical tunneling (QMT) and novel reactions with exceptionally low barriers are at work. Hence, one of the key objectives is to uncover how QMT, where reactions occur through and not over barriers, controls chemical reactivity and selectivity. A second goal is the examination of cryogenic reactions of hydroxycarbenes or enols with carbonyl compounds. Our methods include organic synthesis of starting materials (also isotopically labelled) and products, infrared as well as ultaviolet/visible matrix-isolation spectroscopy, ab initio computations of structures, spectra, and potential energy surfaces as well as QMT rate calculations. We will examine isotope-selective reactions of competing QMT reactions that can be made selective through strategic isotope incorporation. QMT also offers new ways to activate carbon dioxide and even to catalyze reactions. We propose a unifying synthesis of carbohydrates and alpha-amino acids through a common mechanistic scenario, namely a newly discovered hetero-carbonyl-ene reaction of carbenes or enols in the gas phase. Finally, chemistry far from thermodynamic equilibrium is explored with probing the activation and reaction of highly stable molecules under irradiation with energetic electrons, thereby mimicking conditions of the interstellar medium exposed to galactic cosmic rays. This should shed light on the formation of larger “complex organic molecules” found in this medium and often considered as building blocks for life.
Fields of science (EuroSciVoc)
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques. This project's classification has been validated by the project's team.
CORDIS classifies projects with EuroSciVoc, a multilingual taxonomy of fields of science, through a semi-automatic process based on NLP techniques. This project's classification has been validated by the project's team.
Keywords
Programme(s)
- HORIZON.1.1 - European Research Council (ERC) Main Programme
Topic(s)
Funding Scheme
HORIZON-ERC - HORIZON ERC GrantsHost institution
35390 Giessen
Germany