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Updated: Jun 1, 2026

Preparation of a Corannulene-functionalized Hexahelicene by Copper(I)-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
2,2,3,3,5,5,6,6-Octa-p-tolyl-1,4-dioxa-2,3,5,6-tetra-germacyclo-hexane dichloro-methane disolvate
Abstract:
The title compound, C(56)H(56)Ge(4)O(2)·2CH(2)Cl(2) or Tol(8)Ge(4)O(2)·2CH(2)Cl(2) (Tol = p-CH(3)C(6)H(4)), was obtained serendipitously during the attempted synthesis of a branched oligogermane from Tol(3)GeNMe(2) and PhGeH(3). The mol-ecule contains an inversion center in the middle of the Ge(4)O(2) ring which is in a chair conformation. The Ge-Ge bond distance is 2.4418 (5) Å and the Ge-O bond distances are 1.790 (2) and 1.785 (2) Å. The torsion angles within the Ge(4)O(2) ring are -56.7 (1) and 56.1 (1)° for the Ge-Ge-O-Ge angles and -43.9 (1)° for the O-Ge-Ge-O angle.
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