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Updated: May 27, 2026
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
3-(3-Chloro-2-hy-droxy-phen-yl)-1-phenyl-1H-pyrazole-4-carbaldehyde
Abstract:
In the title compound, C(16)H(11)ClN(2)O(2), the pyrazole ring makes dihedral angles of 11.88 (13) and 22.33 (13)° with the 3-chloro-2-hy-droxy-benzene group and phenyl rings, respectively. The phenolic hy-droxy group forms an intra-molecular O-H⋯N hydrogen bond with the imine N atom of the pyrazole unit. The formyl group is virtually coplanar with the pyrazole ring [dihedral angle = 4.5 (19)°] and acts as an acceptor in an intra-molecular C-H⋯O hydrogen bond closing seven-membered ring. In the crystal, adjacent mol-ecules are linked through C-H⋯O hydrogen bonds into infinite chains along the b axis.
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