Methylrhenium trioxide, also known as methyltrioxorhenium, is an organometallic compound with the formula CH3ReO3. It is a volatile, colourless solid that has been used as a catalyst in some laboratory experiments. In this compound, Re has a tetrahedral coordination geometry with one methyl and three oxo ligands. The oxidation state of rhenium is +7.
3D model (JSmol)
CompTox Dashboard (EPA)
|Molar mass||249.24 g/mol|
|Melting point||112 °C (234 °F; 385 K)|
|highly soluble in water|
|Safety data sheet||External MSDS|
|GHS Signal word||Warning|
|H272, H315, H319, H335, H413|
|P210, P220, P221, P261, P264, P271, P273, P280, P302+352, P304+340, P305+351+338, P312, P321, P332+313, P337+313, P362, P370+378, P403+233, P405, P501|
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
|what is ?)(|
- Re2O7 + (CH3)4Sn → CH3ReO3 + (CH3)3SnOReO3
Analogous alkyl and aryl derivatives are known. Compounds of the type RReO3 are Lewis acids, forming both 1:1 and 1:2 adducts with halides and amines.
Methylrhenium trioxide serves as a heterogeneous catalyst for a variety of transformations. Supported on Al2O3/SiO2, it catalyzes olefin metathesis at 25 °C.
In solution, MTO catalyses for the oxidations with hydrogen peroxide. Terminal alkynes yield the corresponding acid or ester, internal alkynes yield diketones, and alkenes give epoxides. MTO also catalyses the conversion of aldehydes and diazoalkanes into an alkene, and the oxidation of amines to N-oxides with sodium percarbonate.
- Herrmann, W. A.; Kratzer R. M.; Fischer R. W. (1997). "Alkylrhenium Oxides from Perrhenates: A New, Economical Access to Organometallic Oxide Catalysts". Angew. Chem. Int. Ed. Engl. 36 (23): 2652–2654. doi:10.1002/anie.199726521.
- Hudson, A. “Methyltrioxorhenium” Encyclopedia of Reagents for Organic Synthesis. John Wiley & Sons: New York, 2002.
- Jain, Suman L.; Joseph, Jomy K.; Sain, Bir (2006). "Rhenium-Catalyzed Highly Efficient Oxidations of Tertiary Nitrogen Compounds to N-Oxides Using Sodium Percarbonate as Oxygen Source". Synlett: 2661–2663. doi:10.1055/s-2006-951487.