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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Three isostructural solvates of a tetrahydrofurochromenone derivative
Balasubramanian Sridhar1, Jagadeesh Babu Nanubolu1, Krishnan Ravikumar1
1X-ray Crystallography Division, CSIR-Indian Institute of Chemical Technology, Hyderabad 500 007, India.
Abstract:
Isostructurality is more likely to occur in multicomponent systems. In this context, three closely related solvates were crystallized, namely, benzene (C27H21BrO6·C6H6), toluene (C27H21BrO6·C7H8) and xylene (C27H21BrO6·C8H10) with methyl 3a-acetyl-3-(4-bromophenyl)-4-oxo-1-phenyl-3,3a,4,9b-tetrahydro-1H-furo[3,4-c]chromene-1-carboxylate, and their crystal structures determined. All three structures belong to the same space group (P-1) and display similar unit-cell dimensions and conformations, as well as isostructural crystal packings. The isostructurality is confirmed by unit-cell and isostructural similarity indices. In each solvate, weak C-H...O and C-H...π interactions extend the molecules into two-dimensional networks, which are further linked by C-H...Br and Br...Br interactions into three-dimensional networks. The conformation of the core molecule is predominantly responsible for governing the isostructurality.
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