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Updated: May 23, 2026
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Pseudopolymorphism in hydroxybenzophenones: the dihydrate of 2,2',4,4'-tetrahydroxybenzophenone
I M R Landre1, F T Martins, J A Ellena
1Laboratório de Cristalografia, Instituto de Química, Universidade Federal de Alfenas, Alfenas, Brazil.
Abstract:
A dihydrate pseudopolymorph of bis(2,4-dihydroxyphenyl)methanone, C(13)H(10)O(5)·2H(2)O, (I), was obtained during polymorphism screening of hydroxybenzophenone derivatives. This structure, in which the molecule sits on a twofold axis, was compared with the known anhydrous form of (I) [Schlemper (1982). Acta Cryst. B38, 554-559]. The role of water in the crystal assembly was established on the basis of the known monohydrate pseudopolymorph of 3,4-dihydroxybenzophenone [Landre, Souza, Corrêa, Martins & Doriguetto (2010). Acta Cryst. C66, o463-o465].
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