Dataset Information

Tricyanidoferrates(-IV) and Ruthenates(-IV) with Non-Innocent Cyanido Ligands.

ABSTRACT: Exceptionally electron-rich, nearly trigonal-planar tricyanidometalate anions [Fe(CN)₃ ]^7- and [Ru(CN)₃ ]^7- were stabilized in LiSr₃ [Fe(CN)₃ ] and AE_3.5 [M(CN)₃ ] (AE=Sr, Ba; M=Fe, Ru). They are the first examples of group 8 elements with the oxidation state of -IV. Microcrystalline powders were obtained by a solid-state route, single crystals from alkali metal flux. While LiSr₃ [Fe(CN)₃ ] crystallizes in P6₃ /m, the polar space group P6₃ with three-fold cell volume for AE_3.5 [M(CN)₃ ] is confirmed by second harmonic generation. X-ray diffraction, IR and Raman spectroscopy reveal longer C-N distances (124-128 pm) and much lower stretching frequencies (1484-1634 cm^-1 ) than in classical cyanidometalates. Weak C-N bonds in combination with strong M-C π-bonding is a scheme also known for carbonylmetalates. Instead of the formal notation [Fe^-IV (CN^- )₃ ]^7- , quantum chemical calculations reveal non-innocent intermediate-valent CN^1.67- ligands and a closed-shell d¹⁰ configuration for Fe, that is, Fe^2- .

SUBMITTER: Jach F

PROVIDER: S-EPMC8362014 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Tricyanidoferrates(-IV) and Ruthenates(-IV) with Non-Innocent Cyanido Ligands.

Jach Franziska F Wagner Frank R FR Amber Zeeshan H ZH Rüsing Michael M Hunger Jens J Prots Yurii Y Kaiser Martin M Bobnar Matej M Jesche Anton A Eng Lukas M LM Ruck Michael M Höhn Peter P

Angewandte Chemie (International ed. in English) 20210615 29

Exceptionally electron-rich, nearly trigonal-planar tricyanidometalate anions [Fe(CN)3 ]7- and [Ru(CN)3 ]7- were stabilized in LiSr3 [Fe(CN)3 ] and AE3.5 [M(CN)3 ] (AE=Sr, Ba; M=Fe, Ru). They are the first examples of group 8 elements with the oxidation state of -IV. Microcrystalline powders were obtained by a solid-state route, single crystals from alkali metal flux. While LiSr3 [Fe(CN)3</sub ...[more]

PMID: 33938602

Similar Datasets

Project description:Diastereomeric dinickel(II) complexes with bis-octaazamacrocyclic 15-membered ligands [Ni(L1-3-L1-3)Ni] (4-6) have been prepared by oxidative dehydrogenation of nickel(II) complexes NiL1-3 (1-3) derived from 1,2- and 1,3-diketones and S-methylisothiocarbohydrazide. The compounds were characterized by elemental analysis, ESI mass spectrometry, and IR, UV-vis, 1H NMR, and 13C NMR spectroscopy. Single crystal X-ray diffraction (SC-XRD) confirmed the isolation of the anti and syn isomers of bis-octaazamacrocyclic dinickel(II) complexes 4a and 4s, the syn-configuration of 5s and the anti-configuration of the dinickel(II) complex 6a. Dimerization of prochiral nickel(II) complexes 1-3 generates two chiral centers at the bridging carbon atoms. The anti-complexes were isolated as meso-isomers (4a and 6a) and the syn-compounds as racemic mixtures of R,R/S,S-enantiomers (4s and 5s). The syn-anti isomerization (epimerization) of the isolated complexes in chloroform was disclosed. The isomerization kinetics of 5a was monitored at five different temperatures ranging from 20 °C to 50 °C by 1H NMR spectroscopy indicating the clean conversion of 5a into 5s. The activation barrier determined from the temperature dependence of the rate constants via the Eyring equation was found to be ΔH‡ = 114 ± 1 kJ mol-1 with activation entropy ΔS‡ = 13 ± 3 J K-1 mol-1. The complexes contain two low-spin nickel(II) ions in a square-planar coordination environment. The electrochemical behavior of 4a, 4s, 5s and 6a and the electronic structure of the oxidized species were studied by UV-vis-NIR-spectroelectrochemistry (SEC) and DFT calculations indicating the redox non-innocent behavior of the complexes. The dinickel(II) complexes 4a, 4s, 5s and 6a/6s were investigated as catalysts for microwave-assisted solvent-free oxidation of cyclohexane by tert-butyl hydroperoxide to produce a mixture of cyclohexanone and cyclohexanol (KA oil). The best value for KA oil yield (16%) was obtained with a mixture of 6a/6s after 2 h of microwave irradiation at 100 °C.

Dataset Information

Tricyanidoferrates(-IV) and Ruthenates(-IV) with Non-Innocent Cyanido Ligands.

Publications

Tricyanidoferrates(-IV) and Ruthenates(-IV) with Non-Innocent Cyanido Ligands.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets