Giving Oxygen Compounds

Methoxydimethylsulfonium and Trimethylsulfoxonium Salts. Alkylating agents react with DMSO at the oxygen. For example, methyl iodide gives methoxydimethylsulfonium iodide (10) as the initial product. The alkoxysulfonium salts are quite reactive and, upon continued heating, either decompose to give carbonyl compounds or rearrange to the more stable trimethylsulfoxonium salts, eg, (11) (eq. 21) (52) ... 

Ethers are relatively stable and unreactivc in many respects, but some ethers react slowly with the oxygen in air to give peroxides, compounds that contain an 0-0 bond. The peroxides from low-molecular-weight ethers such as diisopropyl ether and tetrahydrofuran arc explosive and extremely dangerous, even in tiny amounts. Ethers are very useful as solvents in the laboratory, but they must always be used cautiously and should not be stored for long periods of time. 

Oxygen can be present in naphthenic acids, phenols and furan (analogue structures to thiophene and pyrrole) and higher derivatives. Oxygenated compounds give rise to corrosion and product deterioration. Hydrodeoxygenation is particularly important in the upgrading of biomass. 

Interaction of the yellow hexafluoride with silica to give xenon tetrafluoride oxide must be interrupted before completion (disappearance of colour) to avoid the possibility of formation and detonation of xenon trioxide [1]. An attempt to collect the hexafluoride in fused silica traps at — 20°C after separation by preparative gas chromatography failed because of reaction with the silica and subsequent explosion of the oxygen compounds of xenon so produced [2],... 

Not only water and alcohols, but also other oxygen compounds, are able to react covalently with acylium ions. In the case of hydroxy compounds the product is stabilized by loss of the proton from the hydroxyl group, but certain ethers give an analogous reaction in which the product is stabilized by loss of a carbonium ion.288 Using acetyl chloride with silver perchlorate in nitromethane as the source of acetyl... 

Metathesis of enyne 115 bearing nitrogen or oxygen on alkyne smoothly proceeded to give cyclized compound 116 having an enamide or an enol ether moiety in the molecule. These compounds can be converted into various functionalized compounds ... 

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