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Ferrocene-Supported Compartmental Ligands for the Assembly of 3d/4f Complexes.

ABSTRACT: Site-specific coordination ligands, also known as compartmental ligands, have been used for the preparation of heterometallic complexes. These ligands, by virtue of possessing specific binding sites, can encapsulate different metal ions in their coordination pockets. Such compartmental ligands have been widely used for the preparation of heterometallic 3d/4f complexes which have applications in molecular magnetism. This Review summarizes our efforts in the use of ferrocene-based compartmental ligands for the preparation of heterometallic 3d/4f complexes, some of which are single-molecule or single-ion magnets.

SUBMITTER: Chakraborty A

PROVIDER: S-EPMC7191595 | biostudies-literature | 2020 Apr

REPOSITORIES: biostudies-literature

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Ferrocene-Supported Compartmental Ligands for the Assembly of 3d/4f Complexes.

Chakraborty Amit A Acharya Joydev J Chandrasekhar Vadapalli V

ACS omega 20200413 16

Site-specific coordination ligands, also known as compartmental ligands, have been used for the preparation of heterometallic complexes. These ligands, by virtue of possessing specific binding sites, can encapsulate different metal ions in their coordination pockets. Such compartmental ligands have been widely used for the preparation of heterometallic 3d/4f complexes which have applications in molecular magnetism. This Review summarizes our efforts in the use of ferrocene-based compartmental li ...[more]

PMID: 32363256

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Project description:The use of the N-heterocyclic carbene (NHC) ligands 1,3-bis(2',6'-diethylphenyl)-4,5-(CH2)4-imidazol-2-ylidene (cyIDep), 1,3-bis(2',6'-diethylphenyl)-imidazolin-2-ylidene (sIDep), and its N-mesityl analogue sIMes enables the preparation of the two-coordinate homoleptic iron(I)-NHC complexes [(cyIDep)2Fe][BAr(F)4] (3, Ar(F) denoted for 3,5-di(trifluoromethyl)phenyl) and [(sIDep)2Fe][BAr(F)4] (4) and the T-shaped iron(I)-NHC complex [(sIMes)2Fe(THF)][BPh4] (5, THF = tetrahydrofuran). Complexes 3-5 were prepared via the sequential protocol of control reduction of iron(II) dihalides by KC8 in the presence of the corresponding NHC ligands followed by halide-abstraction with NaBAr4. Spectroscopic characterization, including single-crystal X-ray diffraction studies and (57)Fe Mössbauer spectroscopy, in combination with density functional theory calculations, suggest their high-spin nature. Solution property study (absorption spectroscopy and cyclic voltammetry) indicates that 3 and 5 keep their corresponding two- and three-coordinate nature in THF solution, and 4 might reversibly coordinate a THF molecule to form, presumably, the T-shaped species [(sIDep)2Fe(THF)][BAr(F)4]. The isolation of 3 and 4 demonstrates the accessibility of homoleptic two-coordinate iron(I)-NHC complexes.

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| S-EPMC4613983 | biostudies-other

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