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Updated: Oct 16, 2025
Synthesis of Nine-atom Deltahedral Zintl Ions of Germanium and their Functionalization with Organic Groups
Published on: February 11, 2012
Crystal structure of 9,9-di-ethyl-9H-fluorene-2,4,7-tricarbaldehyde
Pierre Seidel1, Anke Schwarzer1, Monika Mazik1
1Institut für Organische Chemie, Technische Universität Bergakademie Freiberg, Leipziger Str. 29, 09599 Freiberg, Germany.
Abstract:
The title compound, C20H18O3, crystallizes in the space group P21/c with one mol-ecule in the asymmetric unit of the cell. The fluorene skeleton is nearly planar and the crystal structure is composed of mol-ecular layers extending parallel to the (302) plane. Within a layer, one formyl oxygen atom participates in the formation of a Carene-H⋯O bond, which is responsible for the formation of an inversion symmetric supra-molecular motif of graph set R 2 2(10). A second oxygen atom is involved in an intra-molecular Carene-H⋯O hydrogen bond and is further connected with a formyl hydrogen atom of an adjacent mol-ecule. A Hirshfeld surface analysis indicated that the most important contributions to the overall surface are from H⋯H (46.9%), O⋯H (27.9%) and C⋯H (17.8%) inter-actions.
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