Dimethoxymethane

The conventional electrochemical reduction of carbon dioxide tends to give formic acid as the major product, which can be obtained with a 90% current efficiency using, for example, indium, tin, or mercury cathodes. Being able to convert CO2 initially to formates or formaldehyde is in itself significant. In our direct oxidation liquid feed fuel cell, varied oxygenates such as formaldehyde, formic acid and methyl formate, dimethoxymethane, trimethoxymethane, trioxane, and dimethyl carbonate are all useful fuels. At the same time, they can also be readily reduced further to methyl alcohol by varied chemical or enzymatic processes. 

Anesthesia. Materials that have unquestionable anesthetic properties are chloral hydrate [302-17-0] paraldehyde, dimethoxymethane [109-87-5] and acetaldehyde diethyl acetal. In iadustrial exposures, however, any action as an anesthesia is overshadowed by effects as a primary irritant, which prevent voluntary inhalation of any significant quantities. The small quantities which can be tolerated by inhalation are usually metabolized so rapidly that no anesthetic symptoms occur. 

Similaily, dimethoxymethane oi cyclic acetals react to form carbamates in the presence of catalysts. 

Isoprene [78-79-5] (2-methyl-1,3-butadiene) is a colorless, volatile Hquid that is soluble in most hydrocarbons but is practically insoluble in water. Isoprene forms binary azeotropes with water, methanol, methylamine, acetonitrile, methyl formate, bromoethane, ethyl alcohol, methyl sulfide, acetone, propylene oxide, ethyl formate, isopropyl nitrate, methyla1 (dimethoxymethane), ethyl ether, and / -pentane. Ternary azeotropes form with water—acetone, water—acetonitrile, and methyl formate—ethyl bromide (8). Typical properties of isoprene are Hsted in Table 1. 

The reaction of methyl propionate and formaldehyde in the gas phase proceeds with reasonable selectivity to MMA and MAA (ca 90%), but with conversions of only 30%. A variety of catalysts such as V—Sb on siUca-alumina (109), P—Zr, Al, boron oxide (110), and supported Fe—P (111) have been used. Methjial (dimethoxymethane) or methanol itself may be used in place of formaldehyde and often result in improved yields. Methyl propionate may be prepared in excellent yield by the reaction of ethylene and carbon monoxide in methanol over a mthenium acetylacetonate catalyst or by utilizing a palladium—phosphine ligand catalyst (112,113). 

Zn, (CH30)2CH2, BrCH2C02Et, 80-82% yield. Formation of the meth-oxymethyl thioether with dimethoxymethane avoids the use of the carcinogen chloromethyl methyl ether. The reaction forms an intermediate zinc thiolate, which then forms the monothioacetal. 

Diethyl ether with acetone, cyclohexane, ethanol, methanol, methylal (dimethoxymethane), acetonitrile, pentane or p>etroleum ether. 

Even molecules as simple as dimethoxymethane give evidence of anomeric effects. The preferred conformation of dimethoxymethane aligns each C—O bond with a lone-pair orbital of the adjacent oxygen. ... 

Diisopropyl ether, see Isopropyl ether Dimethoxymethane, see Methylal Dimethyl acetamide Dimethylamine... 

Methylal, see Dimethoxymethane Methyl alcohol Methyl amyl alcohol Methyl-n-amyl ketone Methyl bromide 2-Methyl-l -butene... 

Chemical Designations - Synonyms Dimethoxymethane Dimethylformal Formaldehyde dimethylacetat Methylal Methylene dimethyl ether Chemical Formula CHj(OCH3)2. 

Aerosol Fluorination of Dimethoxymethane, 111 Fluorination with Cesium Fluoroxysulfate... 

In 1911, Ame Pictet and Theodor Spengler reported that P-arylethyl amines condensed with aldehydes in the presence of acid to give tetrahydroisoquinolines. Phenethylamine 6 was combined with dimethoxymethane 7 and HCl at elevated temperatures to give tetrahydroisoquinoline 8. Soon after, the Pictet-Spengler reaction became the standard method for the formation of tetrahydroisoquinolines. 

Acetyl-2-Dimethylsulfamylthioxanthene A suspension of 2-dimethylsulfamylthioxanthene (12.22 grams, 0.04 mol) in 60 ml of dimethoxymethane is cooled to 0°C and 17.2 ml of a 2.91 M solution of n-butyl lithium in heptane is added slowly in a nitrogen atmosphere while the temperature is maintained below 10°C. After an additional 10 minutes of stirring, the cooling bath is removed and a solution of 2.96 grams of methyl acetate in 20 ml of di-methoxyethane is added during % hour and then the mixture is stirred at 25°C for an additional 3 hours. The reaction mixture is then treated with 60 ml of ethyl acetate and with 60 ml of a 10% aqueous ammonium chloride solution. The layers are separated and the ethyl acetate layer is washed once with water (25 ml) and then the solvent is removed by distillation. 

In this process, methylal (dimethoxymethane) is used instead of formaldehyde. The advantage of using methylal over formaldehyde is its lower reactivity toward 1-butene than formaldehyde, thus allowing mixed feedstocks to be used. Also, unlike formaldehyde, methylal does not decompose to CO and H2. 

Die Reduktionen werden meist mit einem groBen OberschuB an Reduktionsmitteln in Diathylather, THF, Dimethoxymethan und Dibutylather durchgefiihrt. Zur Reduktion einer Hydrazinocarbonyl-Gruppe sind zwei, zur Bindung eines aktiven Wasserstoff-Atoms ein Hydrid-Aquivalent notwendig. 

In Dimethoxymethan wird z. B. 2-[l-Dimethylamino-propyl-(2)]-l-acetyl-hydrazin zu 2-Athyl-l-[/-dimethylamino-propyl-(2)]-hydrazin (17% d.Th.) reduziert1 2 und 2-Phenyl- 1-acetyl-hydrazin zu 2-Athyl-l-phenyl-hydrazin (89% d.Th.)3 ... 

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