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Updated: May 31, 2026

Modification and Functionalization of the Guanidine Group by Tailor-made Precursors
Published on: April 27, 2017
Redetermination of (E)-N,N'-bis-(4-bromo-phen-yl)formamidine
1Department of Chemistry, Tongji University, Shanghai 200092, People's Republic of China.
Abstract:
In comprison with the previous structural study [Anulewicz et al. (1991 ▶). Pol. J. Chem.65, 465-471], for which only the coordinates of all non-H atoms and of some H atoms were reported, the current redetermination of the title compound, C(13)H(10)Br(2)N(2), additionally reports anisotropic displacement parameters for all non-H atoms and the coordinates of all H atoms, accompanied by higher accuracy of the geometric parameters. Two independent half-mol-ecules are present in the asymmetric unit, which are completed by a twofold rotation axis as symmetry element. In the crystal, inter-molecular N-H⋯N hydrogen bonds link the mol-ecules into dimers. Linear chains parallel to [102] are formed by inter-molecular Br⋯Br inter-actions of 3.4328 (7) Å between two Br atoms of adjacent mol-ecules. The dihedral angles between the benzene rings are 50.05 (15) and 75.61 (11)° in the two independent molecules. Owing to the twofold symmetry of the mol-ecules, H atoms attached to the N atoms are only half-occupied, leading to them being disordered over two positions of equal occupancy.
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