Periodic Reporting for period 2 - X-Fold StereoGen (Catalyst Control over X-Fold Stereogenicity)
Reporting period: 2022-11-01 to 2024-04-30
Stereoisomers are molecules which have the same connectivity, but different arrangements of atoms in space, resulting in distinct properties such as bioactivity. Preparing the desired stereoisomer therefore requires control over the configuration of the groups in the molecule which define stereoisomerism and thus encode molecular topology. Stereoselective catalysis is thereby considered as ideal approach to guide chemical reactions to pathways to give the required stereoisomers. Furthermore, the prospects of minimal side- and byproducts facilitates purifications. While previous catalytic methods were selective for stereogenic units with two configurations, the aim of this EU-funded X-Fold StereoGen project is to catalytically control stereogenic units that encode more than two configurations.
This will allow scientists and ultimately society to catalytically address a larger, nonbinary stereochemical space. The higher-order stereogenic units are controlled with more sustainable synthetic methods to selectively access desired compounds with the required molecular topologies.
The overall objective is to establish the feasibility of catalyst control over higher-order stereogenicity for units with 3-6 configurations. The conceptual relationship between the molecular conformations and higher-order stereogenicity is thereby emphasized. Additionally, the diversity of the increased stereochemical space addressable by catalysis is explored.
This will allow scientists and ultimately society to catalytically address a larger, nonbinary stereochemical space. The higher-order stereogenic units are controlled with more sustainable synthetic methods to selectively access desired compounds with the required molecular topologies.
The overall objective is to establish the feasibility of catalyst control over higher-order stereogenicity for units with 3-6 configurations. The conceptual relationship between the molecular conformations and higher-order stereogenicity is thereby emphasized. Additionally, the diversity of the increased stereochemical space addressable by catalysis is explored.
The work performed so far allowed to establish the feasibility to catalytically control three-, four- and sixfold stereogenicity. Combinations of two catalysts thereby guided oxidation reactions to form each of the three possible stereoisomers. Furthermore, fourfold stereogenicity was addressed for the synthesis of overcrowded alkenes in a two-step process, while catalyst control over sixfold stereogenicity was rendered feasible by forming an aromatic ring.
Besides rotationally restricted compounds, high-valent stereocenters with more than two configurations were addressed by stereoselective catalysis. We expect that by the end of the project, a diversity of higher-order stereogenic units with three-to-six configurations will become catalytically tractable.