Related Experiment Video
Updated: Jun 1, 2026
![Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F60786.jpg&w=3840&q=50)
Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
3-[(E)-3-(2,4-Dichloro-phen-yl)prop-2-en-oyl]-4-hy-droxy-2H-chromen-2-one
Abstract:
In the title compound, C(18)H(10)Cl(2)O(4), the chromen-2-one ring system is almost planar [maximum deviation = 0.028 (1) Å] and is inclined at an angle of 16.35 (4)° with respect to the benzene ring. The C=C bond has an E configuration. The mol-ecular conformation is stabilized by an almost symmetric intra-molecular O⋯H⋯O hydrogen bond and a C-H⋯O inter-action, both of which form S(6) ring motifs. In the crystal structure, mol-ecules are linked into sheets lying parallel to (100) via inter-molecular C-H⋯O hydrogen bonds. The crystal packing is further consolidated by π-π stacking inter-actions [centroid-to-centroid separation = 3.6615 (6) Å].
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