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DOI: 10.1055/a-1293-9867
Determining the Relative Configuration of Propargyl Cyclopropanes by Co-Crystallization
This work was supported by DFG grant RI 1063/17-1.
Abstract
Determining the diastereoselectivity of new synthetic molecules can be a challenge when NMR methods fail and the compounds are difficult to crystallize. Encapsulating organic crystals can be used to overcome this challenge. Here we show that the diastereomeric configuration of racemic mixtures of propargyl cyclopropanes can be determined by co-crystallization with 1,3,5,7-tetrakis(2-bromo-4-methoxyphenyl)adamantane and X-ray crystallography. Three crystal structures are reported that unambiguously identify the products of Fe-catalyzed cyclopropanations as cis- or trans-isomers. These findings expand the scope of co-crystallization with tetraaryladamantanes as a method to determine the stereochemical configuration of organic molecules that are difficult to crystallize by themselves.
Key words
stereochemistry - crystallization - diastereomers - structure elucidation - X-ray crystallographySupporting Information
- Supporting information for this article is available online at https://doi.org/10.1055/a-1293-9867.
- Supporting Information
Publikationsverlauf
Eingereicht: 18. September 2020
Angenommen nach Revision: 20. Oktober 2020
Accepted Manuscript online:
20. Oktober 2020
Artikel online veröffentlicht:
26. November 2020
© 2020. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial-License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)
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