2-Amino-4-ferrocenyl-5-oxo-5,6,7,8-tetra-hydro-4H-chromene-3-carbo-nitrile monohydrate.

In the title hydrate, [Fe(C(5)H(5))(C(15)H(13)N(2)O(2))]·H(2)O, the pendent ferrocenyl substituent is significantly rotated against the chromene backbone, with a torsion angle of 56.8†(2)°. Rotational disorder is observed in one of the Cp rings of the ferrocenyl substituents. The crystal packing is consolidated by a network of O-H⋯N, O-H⋯O, N-H⋯O and N-H⋯π hydrogen bonds, prominently involving a solvent water mol-ecule. The water mol-ecule functions as both a hydrogen-bond donor and acceptor, bridging adjacent mol-ecules, leading to the formation of a layer with a distinctive hydrogen-bonded motif propagating parallel to the bc plane.