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Crystal structure of di-bromido-bis-(1,3-dibenzyl-1,3-diazinan-2-one-κO)cobalt(II)
Eduard Rais1, Ulrich Flörke1, René Wilhelm1
1Department Chemie, Universität Paderborn, Warburgerstrasse 100, 33098 Paderborn, Germany.
Abstract:
The unit cell of the title complex, [CoBr2(C18H20N2O)2], contains 1.5 formula units per asymmetric unit with one mol-ecule sitting on a general site and a second one halved by a crystallographic twofold rotation axis passing through the Co(II) cation. Both Co(II) atoms are coordinated in a distorted tetra-hedral manner by two Br(-) ligands and two O atoms of the pyrimidinone (OPyr) groups. The Br-Co-Br coordination angles are similar [115.46 (4) and 115.20 (5)°], while the O-Co-O angles differ slightly more [102.26 (18) and 98.1 (2)°]. Similarly, the Co-Br bond lengths are almost identical [2.3721 (9), 2.3757 (10) and 2.3809 (10) Å], with a larger difference between the Co-O bond lengths [1.929 (4), 1.926 (4) and 1.955 (4) Å]. The three independent OPyr groups present envelope conformations, with three C and two N atoms lying in well defined planes with maximum deviations from the least-squares planes of 0.047, 0.031 and 0.036 Å, and the external-most C atoms protruding by 0.654 (6), 0.643 (7) and 0.656 (6) Å out of the planes. The dihedral angles between the planar fractions of the OPyr planes are 50.5 (1)° for the nonsymmetric mol-ecule and 49.7 (1)° for the symmetric one. Non-covalent inter-actions are of the C-H⋯Br type and they are weak, hardly shorter than van der Waals radii, with an H⋯Br distance range of 3.00-3.04 Å. The inter-molecular inter-actions define chains parallel to [101].
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