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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
3,3'-[(4-Nitro-phen-yl)methyl-ene]bis-(4-hy-droxy-2H-chromen-2-one)
N Ravikumar1, G Gopikrishna, K Anand Solomon
1Sankar Foundation Research Institute, Naiduthota, Vepagunta, Visakhapatnam, Andhra Pradesh 530 047, India.
Abstract:
The molecular conformation of the title compound, C(25)H(15)NO(8), is stabilized by strong intramolecular O-H⋯O hydrogen bonds, resulting in the formation of S(1) (1)(7) ring motifs. In the crystal, π-π stacking inter-actions are observed between adjacent nitrobenzene and pyranone rings with a centroid-centroid distance of 3.513 (12) Å. The dihedral angles between the nitrobenzene ring and the coumarin ring systems are 65.61 (8) and 66.11 (8)° while the coumarin ring systems are inclined at 65.69 (8)°.
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