Synthesis, Structural Elucidation, Cyclic Voltammetry, and Theoretical Modelling of 2‐Ferrocenyl‐4H‐benzo[e][1,3]thiazines and 2‐Aryl‐4H‐ferroceno[e][1,3]thiazines

Abstract

2-Ferrocenyl-4H-benzo[e] [1,3]thiazine and its 6,7-dimethoxy derivative were prepared by a Bischler-Napieralskitype annulation of the Mannich adducts of ferrocenecarboxamide, formaldehyde, and the corresponding thiophenol. A more efficient synthetic pathway, comprising a directed lithiation/iodination sequence followed by standard functionalgroup transformations and a final copper-catalyzed cyclization, was elaborated to convert [(dimethylamino)methyl]ferrocene into racemic mixtures of the first representatives of planar-chiral 4H-ferroceno[e][1,3]thiazines. A similar strategy with 2-iodobenzyl bromide as the precursor enabled a highly improved

Ferrocene-Containing Impiridone (ONC201) Hybrids: Synthesis, DFT Modelling, In Vitro Evaluation, and Structure–Activity Relationships

“…In the final step, the targeted impiridones type 7 were obtained in moderate-to-good overall yields ( Scheme 1 ) by the base-catalysed condensation of the selected pair of compounds 4 and 6 performed under standard conditions (NaOMe in MeOH at reflux temperature) [ 24 ]. Since the ferrocene-based amines 1d – g are not commercially available, we accessed these reagents by well-established described synthetic routes [ 36 , 37 , 38 , 39 ].…”

“…All chemicals (expect 1d – g ) were obtained from commercially available sources (Aldrich, St. Louis, MO, USA, Fluka) and used without further purification, expect solvents. Ferrocenylalkylamines 1d – g were synthesised by well-established reported procedures: 1d [ 37 ]; 1e [ 38 ]; 1f [ 39 ]; 1g [ 40 ]. Methanol and triethylamine (TEA) were distilled from sodium, while THF was distilled from sodium benzophenone.…”

Haloferrocenes: Syntheses and Selected Reactions

“…In the intramolecular substitution, thioamides such as 113 were converted into ferrocenothiazines like 114 in up to 93% yield in the presence of copper(I) iodide and N,N′-dimethylethylenediamide (DMEDA) (10 mol% each) (Scheme 37). 73 Scheme 37 Copper-catalyzed heteroanellation 73 There are some interesting cases of copper-mediated reactions of haloferrocenes leading to ferrocenes with new carbon-carbon bonds. An early example was provided by Rosenblum et al, who prepared [2.2]ferrocenophane-1,13diyne (117) from 1-iodo-1′-ethynylferrocene (115) in a Stephens-Castro coupling reaction via copper acetylide 116 in an overall yield of 11% from 115 (Scheme 38).…”

2,3-Dihydroferroceno[3,4]pyrrolo[2,1-b]thiazol-5(8b)-ones: Synthesis, Structure and DFT Study on the Mechanism of Chemo- and Diastereoslective Annulations of (Sp)-2-Formylferrocenecarbonyl Fluoride and (Sp)-2-Formylferrocenecarboxylic Acid

“…As a continuation of our program expanding the scope of ferrocene-containing heterocycles with potential biological relevance, we envisaged a preliminary study on the synthetic accessibility and structural characteristics of the first members of ferroceno[3,4]pyrrolo[2,1-b]thiazol-5(8bH)-ones. These organometallics, comprising the elements of planar- and central chirality, represent a novel class of ferrocene-fused heterocycles with well-defined stereostructures [ 12 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ]. The diverse molecular architectures of known ferroceno-heterocycles have been assembled by a variety of synthetic methodologies including conventional organic heterocyclisations [ 12 , 17 , 18 , 19 ] and protocols based on transition metal-catalysed CH-activation [ 20 , 21 ], alkyne-mediated annulations [ 22 , 23 ], cross-coupling reactions [ 24 ], metal-free radical cyclisation [ 25 ] as well as iron-incorporation in the late-stage construction of the ferrocene moiety [ 26 ].…”