News05.12.2017Publication of "Polymorphism in secondary squaramides: on the importance of π–interactions involving the four membered ring" |
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Dr. Rafel Prohens, responsible of Polymorphism and Calorimetry Technology of CCiTUB, and Dra. Mercè Font of X-Ray Diffraction technology, have participated as co-authors in the publication of the article: "Polymorphism in secondary squaramides: on the importance of π–interactions involving the four membered ring" in the journal "CrystEngComm"of the Royal Society of Chemistry, on 1st of December 2017. The summary of the article is as follows: "We report four new squaric acid derivatives X-ray solid state structures, i.e. three polymorphs of 3,4-bis((2-(dimethylamino)ethyl)amino)cyclobut-3-ene-1,2-dione (1a-c) and a co-crystal of compound 1 and resorcinol (2). All structures form interesting supramolecular assemblies in the solid state that have been analyzed using high level DFT calculations and molecular electrostatic potential (MEP) surface calculations. A combination of H-bonding and π–π stacking interactions of the cyclobutenedione rings are crucial for the formation of the supramolecular assemblies in the solid state. Moreover, unusual antiparallel CO•••CO interactions observed in the X-ray structure of one of the polymorphs of 1 and the lp–π interactions between one oxygen atom of resorcinol and the squaramide ring in 2 have been characterized using the Bader’s theory of “atoms-in-molecules” (AIM)." For more information, you can access the following link:[+]. |
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