authors |
Petrovski, Z; Pillinger, M; Valente, AA; Goncalves, IS; Hazell, A; Romao, CC |
nationality |
International |
journal |
JOURNAL OF MOLECULAR CATALYSIS A-CHEMICAL |
author keywords |
molybdenum; nitrogen ligands; oxide complexes; olefin epoxidation; X-ray diffraction |
keywords |
ALKENE EPOXIDATION; ALKYL HYDROPEROXIDES; OLEFIN EPOXIDATION; OXIDATION; REACTIVITY; ADDUCTS; LIGAND |
abstract |
Dioxomolybdenum(VI) complexes of the type MoO(2)X(2)L containing ethylenediimine ligands were prepared in good yield by reaction of MoO(2)X(2)(THF)(2) (X = Cl, Br) with the bidentate ligands Ph(2)C=NCH(2)CH(2)N=CPh(2) (PBED) or PhCH=NCH(2)CH(2)N=CHPh (BED). The crystal structure of MoO(2)Br(2)(BED) was determined by X-ray diffraction. The dichloro complexes were active as catalysts for the reaction of cyclooctene with tert-butyl hydroperoxide (TBHP) at 55 degreesC yielding epoxycyclooctane as the only product up to 7 h after the start of the reaction. The highest initial activity was obtained with MoO(2)Cl(2)(BED) (63 mol mol(Mo)(-1) h(-1)). Other olefins were also tested, and activities decreased in the order cyclooctene > cycloclodecene > (R)-(+)-limonene > cyclohexene > trans-2-octene > 1-octene. The dibromo complexes exhibited much lower activities than the dichloro complexes for the epoxidation of cyclooctene. (C) 2004 Elsevier B.V. All rights reserved. |
publisher |
ELSEVIER SCIENCE BV |
issn |
1381-1169 |
year published |
2005 |
volume |
227 |
issue |
1-2 |
beginning page |
67 |
ending page |
73 |
digital object identifier (doi) |
10.1016/j.molcata.2004.10.004 |
web of science category |
Chemistry, Physical |
subject category |
Chemistry |
unique article identifier |
WOS:000226424000009
|