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Efficient Construction of Drug-like Bispirocyclic Scaffolds Via Organocatalytic Cycloadditions of α-Imino γ-Lactones and Alkylidene Pyrazolones
Published on: February 7, 2019
3-(3-Oxo-1,3-dihydroisobenzofuran-1-ylidene)pentane-2,4-dione
Jaime Portilla1, Jairo Quiroga, Justo Cobo
1Grupo de Investigación de Compuestos, Heterociclícos, Departamento de Química, Universidad de Valle, AA 25360, Colombia.
Abstract:
In the title compound, C(13)H(10)O(4), prepared by the condensation reaction between phthalic anhydride and pentane-2,4-dione, one of the acetyl groups in the pentane-2,4-dione fragment is almost coplanar with the isobenzofuran ring system, while the other group is twisted out of this plane by almost 80 degrees . The corresponding C-C and C-O distances in the two acetyl units are consistent with dipolar delocalization into the coplanar unit only. There is no supramolecular aggregation of the molecules, but a number of rather short intermolecular contacts of C-H...O, O...O and O...C types occur.
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