Methyltrioxorhenium. An air-stable compound containing a carbon-rhenium bond

MTO Schiff‐Base Complexes: Synthesis, Structures and Catalytic Applications in Olefin Epoxidation

“…All products were isolated as orange (1)(2)(3)(4) or red (5) crystals in yields higher than 80 %. In comparison to many N-coordinated Lewis base adducts, which are considerably more sensitive to the presence of moisture and temperature than MTO itself, [9e, 10a,b, 14, 15] compounds 1-5 show good stability at room temperature both in the solid state and in solution.…”

“…[23] Compounds 1-5 were prepared as follows: A solution of [(CH 3 )ReO 3 ] (0.2 g, 0.8 mmol) in diethyl ether (5 mL) was added dropwise to an equally concentrated solution of ligand (0.8 mmol) in diethyl ether (5 mL) whilst stirring at room temperature. After 15 min the yellow solution was concentrated to about 3 mL under an oil pump vacuum and the orange (1)(2)(3)(4) or orange-red (5) precipitate was collected by filtration, washed with n-hexane and dried under reduced pressure. 161.23,148.17,133.16,132.25,129.34,128.97,126.87,121.07,119.09,118.98,; IR (KBr): see Tables 1 and 2; MS (FAB): m/z (%) 197.9 (100) [M + ÀMTO]; elemental analysis calcd (%) for C 14 H 14 NO 4 Re (446.46): C 37.66,H 3.14,N 3.14;found: C 37.64,H 3.14,N 3.15 19, 136.92, 133.02, 132.12, 129.92, 120.82, 119.04, 118.84, 117.22 (aryl-C) 161.03, 146.68, 133.35, 132.32, 129.37, 122.32, 119.07, 118.85, 117.17 (aryl-C) 159.89, 158.72, 140.28, 132.84, 131.92, 122.02, 118.96, 118.71, 117.15, 114.47 (aryl-C) 37, 151.41, 148.30, 145.11, 136.88, 129.85, 123.52, 120.80, 118.94, 116.25, 114.41, 55.96 Single-crystal X-ray structure determination of Complexes 1-5: Details of the X-ray experiment, crystal parameters, data collections and refinements are summarised in Table 8.…”

“…Methyltrioxorhenium (MTO), which was considered as a mere curiosity when it was first described, [1] has become an almost unparalleled success story since it became available in larger amounts from improved syntheses.…”

Kostengünstige, effiziente und umweltfreundliche Synthese des vielseitigen Katalysators Methyltrioxorhenium (MTO)

“…[2] MTO wurde erstmals in einem zeitaufwändigen Prozess hergestellt, der nur geringe Ausbeuten im Milligramm-Bereich lieferte. [3] Ausführliche Studien in Industrie und Hochschule belegten, dass MTO der aktivste bekannte Katalysator für die Olefin-Epoxidierung ist. MTO hat nicht nur zahlreiche Anwendungen in der Oxidationskatalyse gefunden, es katalysiert auch andere Reaktionen wie die Olefin-Metathese und die Aldehyd-Olefinierung.…”

A Rapid and Efficient Synthesis of Quinone Derivatives: Ru(II)- or Ir(I)-Catalyzed Hydrogen Peroxide Oxidation of Phenols and Methoxyarenes

“…Also, aqueous hydrogen peroxide is a stable reagent, provided it is handled and stored in the proper manner. [10] During the last decade, many catalytic methods of oxidation have been developed to oxidize phenols or methoxybenzenes to the corresponding quinones using H 2 O 2 as an oxidant with diphenyl diselenide, [11] methylrhenium trioxide (MTO), [12] polymer-supported MTO, [13] I 2 or the HI-H 2 SO 4 system, [14] a Cu(II)-resin system, [15] and TiO 2 -SiO 2 mixed oxides. [16] We now report a new and highly selective synthesis of quinones from dihydroxybenzene and methoxybenzene derivatives with the involvement of H 2 O 2 as the oxidant and Ru(II)(pybox-dh)(pydic) or Ir[(coe) 2 Cl] 2 or Ir[(cod)Cl] 2 as catalyst.…”