authors |
Gomes, AC; Neves, P; Gago, S; Valente, AA; Goncalves, IS; Pillinger, M |
nationality |
International |
journal |
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY |
author keywords |
Molybdenum; Half-sandwich complexes; Oxido ligands; Cyclopentadienyl ligands; Layered compounds |
keywords |
OLEFIN EPOXIDATION; MOLYBDENUM; FERROCENE; COMPLEX |
abstract |
A Zn,Al layered double hydroxide (LDH) with [Cp*MoO3](-) (Cp* = eta(5)-C5Me5) anions in the interlayer has been prepared by a direct coprecipitation method. The intercalated LDH and the mixed metal oxide (MMO) obtained after its calcination were characterized by elemental and thermogravimetric analyses, powder X-ray diffraction (PXRD), FT-IR and FT-Raman spectroscopy, C-13 and Al-27 MAS NMR, and scanning electron microscopy. The observed basal spacing of 17.1 angstrom for the LDH Zn,Al-Cp*MoO3 (corresponding to a gallery height of 12.3 angstrom) suggests that the guest anions self-assemble into dimers via offset face-to-face Cp*center dot center dot center dot Cp* interactions, which facilitates hydrogen-bonding interactions between the oxido ligands of the complexes and the layer hydroxyl groups, while positioning the hydrophobic aromatic rings towards the center of the galleries. Calcination of Zn,Al-Cp*MoO3 at 550 degrees C under air gave an MMO comprising well-dispersed ZnO, alpha-ZnMoO4 and ZnAl2O4 (spinel) oxides in a molar of ca. 1.4:1.6:1. The MMO exhibited catalytic activity for the epoxidation of cis-cyclooctene with tert-butylhydroperoxide (TBHP) as terminal oxidant, with quantitative yield of the epoxide being achieved within 24 h at 85 degrees C. |
publisher |
WILEY-V C H VERLAG GMBH |
issn |
1434-1948 |
isbn |
1099-0682 |
year published |
2020 |
volume |
2020 |
issue |
25 |
beginning page |
2408 |
ending page |
2416 |
digital object identifier (doi) |
10.1002/ejic.202000127 |
web of science category |
Chemistry, Inorganic & Nuclear |
subject category |
Chemistry |
unique article identifier |
WOS:000533565800001
|