143037-14-3Relevant articles and documents
Synthesis and properties of homogeneous models of the Re2O7/Al2O3 metathesis catalyst
Commereuc,Doledec
, p. 125 - 140 (2008/10/08)
Soluble complexes, including aluminum coordinated with a perrhenate and a 4-substituted-2-6-di-tert-butylphenoxy ligand or a CH2- or S-ortho bridged-4,4'-di-tert-butyldiphenoxy ligand, were synthesized and characterized. The reaction of (ArO)2Al-Cl with AgReO4 resulted in new complexes (ArO)2Al-OReO3 (A), which showed a low activity in the metathesis of 2-pentene. Complexes (ArO)2Al-R (R = isobutyl, ethyl) reacted with Re2O7 in tetrahydrofuran or dioxane, generating type B complexes including oligomeric linkages such as O3Re-[Al(OAr)-O]2-ReO3. Some of these complexes, unstable even under an argon atmosphere, were identified after stabilization with a Lewis base like quinuclidine or bipyridine. Before their stabilization, they exhibited a rather high activity in the metathesis of 2-pentene, with turnover frequency of 100/min, and functional olefins (diallylether, diallylsulfide). Upon reaction with (ArO)2Al-R in an ether solvent, A complexes might be converted into B complexes. The high activity of B complexes was associated with the presence of Al-O-Al linkages that are known to induce a powerful bidendate Lewis acidity.