5-(Phenyldiazenyl)tropolone

Abstract

The title compound [systematic name: (E)-2-hy­droxy-5-(phenyl­diazen­yl)cyclo­hepta-2,4,6-trien-1-one], C13H10N2O2, is essentially planar with an r.m.s. deviation of 0.036 (2) Å and a dihedral angle of 1.57 (8)° between the phenyl and tropolone rings. In the crystal, mol­ecules are linked by pairs of O—H⋯O hydrogen bonds into inversion dimers. The dimers are further connected by C—H⋯O hydrogen bonds and π–π stacking inter­actions, with centroid–centroid distances of 3.6934 (9) and 3.6282 (9) Å.

Negative Result: Assessing tropolone and its derivatives as chemical fingermark developers on paper surfaces

“…The choice of a methoxy-and nitro-substituted diazonium salt was made to evaluate the influence of including either an electron-donating or electronwithdrawing functional group, the latter of which may trigger formation of a push-pull chromophore, and thus a more intensely-coloured dye. Azo dye formation using tropolone nucleophiles has been shown previously using an analogous methodology in other applications [7][8][9], however this work represents the first attempt to apply this chemistry in a forensic context.…”

Crystal structure of trans-bis((E)-7-oxo-4-(phenyldiazenyl)cyclohepta-1,3,5-trien-1-olato)-κ2 O,O′)-bis(pyridine-κN)cobalt(II), C36H28CoN6O4

“…Past investigations have highlighted the fact that the tropolone-type ligands (TropH) are very effective chelating agents and have a wide range of chemical applications [1][2][3][4]. The complexation of these ligands to transition metal centres is however not a novel notion, with the tropolonato anion forming a five-membered chelating ring resulting in a smaller bite angle than that of the β-diketonato analogues [1,5].…”

“…The molecules are held together by a head-to-tail π· · · π stacking interaction involving the phenyl-azotropolonato ligands, with a distance of 3.638 Å between best planes defined by the ligands. While free phenyl-azotropone [3] was found to be essentially planar, the cobalt(II) complex displays bending and twisting of the phenyl-azotropolonato back-bone. In the structure of the title compound an additional π· · · π interaction was observed between pyridine ligands with a distance of 2.617 Å, generating a three-dimensional supramolecular network.…”

“…5-(Phenyldiazenyl)tropolone was synthesized according to the previously published method [3]. 5-(Phenyldiazenyl)tropolone (452 mg, 2.0 mmol) and pyridine (162 µL, 2.0 mmol) were added to a solution of Co(CH 3 COO) 2 ·4H 2 O (249 mg, 1.0 mmol) in EtOH:H 2 O (40 ml, 1:1).…”