Oxidomolybdenum complexes for acid catalysis using alcohols as solvents and reactants

authors	Gomes, AC; Neves, P; Cunha-Silva, L; Valente, AA; Goncalves, IS; Pillinger, M
nationality	International
journal	CATALYSIS SCIENCE & TECHNOLOGY
keywords	LEWIS-BASE ADDUCTS; RING-OPENING REACTIONS; MOLYBDENUM(VI) DICHLORIDE DIOXIDE; VALENT OXO-MOLYBDENUM; OLEFIN EPOXIDATION; DIOXOMOLYBDENUM(VI) COMPLEXES; THIOCYANATODIOXOMOLYBDENUM(VI) COMPLEXES; STRUCTURAL-CHARACTERIZATION; CYCLOOCTENE EPOXIDATION; EFFICIENT CATALYSTS
abstract	The application field of dichloridodioxidomolybdenum (VI) chelate complexes, which have been intensively investigated as catalysts for liquid-phase olefin epoxidation, is broadened to encompass acid catalysis, in particular, alcoholysis and acetalisation reactions. Complex [MoO2Cl2(L)] (1) with L = 4,4'-di-tert-butyl-2,2'-bipyridine was chosen as (pre)catalyst. Depending on the reaction conditions, 1 either remained structurally intact or was transformed into different metal species, the structures of which were determined on the basis of single-crystal X-ray diffraction, spectroscopic techniques (FT-IR and H-1 NMR), and elemental analysis. The first example of a mixed-ligand complex of the type [MoO2X(OR)(L)] (X = halide) is disclosed. This complex is one of only a handful of complexes known to date that exhibit an all-cis configuration instead of the usual cis-oxido, trans-X, cis-L configuration (X = anionic ligand). Mechanistic considerations of the formation of the metal species are made.
publisher	ROYAL SOC CHEMISTRY
issn	2044-4753
year published	2016
volume	6
issue	13
beginning page	5207
ending page	5218
digital object identifier (doi)	10.1039/c5cy02052b
web of science category	Chemistry, Physical
subject category	Chemistry
unique article identifier	WOS:000378734700060