Methylrhenium trioxide
Names
IUPAC name
Methyl(trioxo)rhenium(VII)
Other names
Methyltrioxorhenium(VII)
Identifiers
Abbreviations
MTO
ChemSpider
ECHA InfoCard
100.202.821
UNII
InChI=1S/CH3.3O.Re/h1H3;;;;
N Key: PQTLALPZRPFYIT-UHFFFAOYSA-N
N InChI=1/CH3.3O.Re/h1H3;;;;/rCH3O3Re/c1-5(2,3)4/h1H3
Key: PQTLALPZRPFYIT-YHFCCQKIAF
Properties
CH3 ReO3
Molar mass
249.239 g·mol−1
Appearance
white powder
Melting point
112 °C (234 °F; 385 K)
highly soluble in water
Hazards
GHS labelling :
Warning
H272 , H315 , H319 , H335 , H413
P210 , P220 , P221 , P261 , P264 , P271 , P273 , P280 , P302+P352 , P304+P340 , P305+P351+P338 , P312 , P321 , P332+P313 , P337+P313 , P362 , P370+P378 , P403+P233 , P405 , P501
Safety data sheet (SDS)
External MSDS
Except where otherwise noted, data are given for materials in their
standard state (at 25 °C [77 °F], 100 kPa).
Chemical compound
Methylrhenium trioxide , also known as methyltrioxorhenium(VII) , is an organometallic compound with the formula CH3 −ReO3 . It is a volatile, colourless solid that has been used as a catalyst in some laboratory experiments. In this compound, rhenium has a tetrahedral coordination geometry with one methyl and three oxo ligands . The oxidation state of rhenium is +7.
Synthesis
Methylrhenium trioxide is commercially available. It can be prepared by many routes, a typical method is the reaction of rhenium heptoxide and tetramethyltin :[1]
Re2 O7 + (CH3 )4 Sn → CH3 ReO3 + (CH3 )3 Sn−O−ReO3
Analogous alkyl and aryl derivatives are known. Compounds of the type R−ReO3 are Lewis acids , forming both 1:1 and 1:2 adducts with halides and amines.
Uses
Methylrhenium trioxide serves as a heterogeneous catalyst for a variety of transformations. Supported on alumina /silica , it catalyzes olefin metathesis at 25 °C.
In solution, methylrhenium trioxide catalyses for the oxidations with hydrogen peroxide . Terminal alkynes yield the corresponding carboxylic acid or ester , internal alkynes yield diketones , and alkenes give epoxides . Methylrhenium trioxide also catalyses the conversion of aldehydes and diazoalkanes into an alkene,[2] and the oxidation of amines to N -oxides with sodium percarbonate .[3]
References
^ 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, Andrew; Betz, Daniel; Kühn, Fritz E.; Jiménez-Alemán, Guillermo H.; Boland, Wilhelm (2013-09-16). "Methyltrioxorhenium" . Encyclopedia of Reagents for Organic Synthesis . John Wiley & Sons, Ltd. doi :10.1002/047084289x.rn00017.pub3 . ISBN 978-0-471-93623-7 .
^ 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 .
Rhenium(0)
Rhenium(I)
Rhenium(II) Rhenium(III) Rhenium(IV) Rhenium(V) Rhenium(VI) Rhenium(VII)