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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
6-Chloro-4-(2-phenyl-ethen-yl)chroman-2-one
1Department of Chemistry, Kyonggi University, San 94-6, Iui-dong, Yeongtong-gu, Suwon 443-760, Republic of Korea.
Abstract:
The title compound, C(17)H(13)ClO(2), was obtained from the oxidation of 6-chloro-4-(2-phenyl-ethen-yl)chroman-2-ol, which was synthesized by the reaction of of (E)-3-(5-chloro-2-hy-droxy-phen-yl)acryl-aldehyde with styrylboronic acid using diethyl-amine as a catalyst. The six-membered pyran-one ring of the chromane system has a screw-boat conformation. The dihedral angle between the least-squares planes of the chromane ring system and the styryl group is 85.28 (9)°.
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