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Updated: Aug 15, 2026

Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyl(tropone)iron
Published on: August 12, 2019
Co-crystallized cis and trans isomers of dichlorobis(2-picolylamine)iron(II)
Karl W Törnroos1, Dmitry Chernyshov, Marc Hostettler
1Department of Chemistry, University of Bergen, Allégt. 41, 5007 Bergen, Norway. karl.tornroos@kj.uib.no
Abstract:
The octahedral cis and trans isomers of dichlorobis(2-picolylamine)iron(II), [FeCl2(C6H8N2)2], co-crystallize in a 1:1 ratio. The cis isomer lies on a twofold axis, whereas the trans isomer lies on an inversion centre. The structure is fully ordered, with both Fe atoms in a pure high-spin state. The Fe, Cl and N(H2) atoms of both isomers lie in the same plane, allowing all Cl and amine H atoms to be engaged in extensive two-dimensional hydrogen bonding. The hydrogen-bonded layers are interconnected through pi-pi interactions between the pyridine rings. Searches in the Cambridge Structural Database uncover very few examples of such isomer co-existence.
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