Synthesis and catalytic properties in olefin epoxidation of dioxomolybdenurn(VI) complexes bearing a bidentate or tetradentate salen-type ligand

• Type: Article in International Scientific Journal
• Date: 2007

Authors

Sofia M Bruno (Author) Other; Salete S Balula (Author) Other; Anabela A Valente (Author) Other; Filipe A A Almeida Paz (Author) Other; Martyn Pillinger (Author) Other; Carla Sousa (Author) Other; Jacek Klinowski (Author) Other; Cristina Freire (Author) FCUP; Paulo Ribeiro Claro (Author) Other; Isabel S Goncalves (Author) Other

Journal

Title: Journal of Molecular Catalysis A: Chemical

Vol. 270

Pages: 185-194

ISSN: 1381-1169

Publisher: Elsevier B.V.

Indexing

ISI Web of Knowledge - 44 Citations

Scopus - 46 Citations

Scientific classification

FOS: Natural sciences > Chemical sciences

Other information

Authenticus ID: P-004-9TY

DOI: 10.1016/j.molcata.2007.01.050

Abstract (EN): The monomeric cis-dioxomolybdenum(VI)complexes [MoO(2)(oep-saldpen)] and [MoO(2)Cl(2)(oep-H(2)saldpen)], with a tetradentate [N(2)(imine)O(2)] and bidentate [N(2)(imine)] salen-type ligand functionalised with two pyrrole derivative pendant arms [oep-H(2)saldpen = 1,2-diphenylethylenebis(3-oxyethylpyrrole)salicylideneimine], were synthesised and characterised by (1)H NMR, IR and Raman spectroscopy. The solid-state structure of the free ligand oep-H(2)saldpen was determined by single crystal X-ray diffraction. Assignment of the vibrational spectra of the molybdenum complexes was supported by carrying out ab initio calculations for the possible isomers using [MoO(2)(salen)] and [MoO(2)Cl(2)(H(2)salen)] as model compounds [H(2)salen = N,N '-ethylenebis(salicylideneimine)]. The oep-saldpen complexes were examined as catalysts for the epoxidation of cyclooctene, (R)(+)-limonene, styrene, alpha-pinene, and cis and trans-beta-methylstyrene, with tert-butyl hydroperoxide as the oxidant. Both complexes exhibited high selectivity for the epoxidation reaction, with the bis(chloro) complex being always the more active of the two.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10