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Updated: Dec 24, 2025

Preparation of 6-aminocyclohepta-2,4-dien-1-one Derivatives via Tricarbonyltroponeiron
Published on: August 12, 2019
Mono-, Di- and Tetra-iron Complexes with Selenium or Sulphur Functionalized Vinyliminium Ligands: Synthesis,
Gabriele Agonigi1, Lucinda K Batchelor2, Eleonora Ferretti3
1Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via G. Moruzzi 13, I-56124 Pisa, Italy.
Abstract:
A series of diiron/tetrairon compounds containing a S- or a Se-function (2a-d, 4a-d, 5a-b, 6), and the monoiron [FeCp(CO){SeC1(NMe2)C2HC3(Me)}] (3) were prepared from the diiron μ-vinyliminium precursors [Fe2Cp2(CO)( μ-CO){ μ-η1: η3-C3(R')C2HC1N(Me)(R)}]CF3SO3 (R = R' = Me, 1a; R = 2,6-C6H3Me2 = Xyl, R' = Ph, 1b; R = Xyl, R' = CH2OH, 1c), via treatment with S8 or gray selenium. The new compounds were characterized by elemental analysis, IR and multinuclear NMR spectroscopy, and structural aspects were further elucidated by DFT calculations. The unprecedented metallacyclic structure of 3 was ascertained by single crystal X-ray diffraction. The air-stable compounds (3, 4a-d, 5a-b, 6) display fair to good stability in aqueous media, and thus were assessed for their cytotoxic activity towards A2780, A2780cisR, and HEK-293 cell lines. Cyclic voltammetry, ROS production and NADH oxidation studies were carried out on selected compounds to give insights into their mode of action.
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