1.1- Dimethoxyethane

Many substances have more than one ether linkage Two such compounds often used as solvents are the diethers 1 2 dimethoxyethane and 1 4 dioxane Diglyme also a commonly used solvent is a triether... 

Ma.nufa.cture. In general, manufacture is carried out in batch reactors at close to atmospheric pressure. A moderate excess of finely divided potassium hydroxide is suspended in a solvent such as 1,2-dimethoxyethane. The carbonyl compound is added, followed by acetylene. The reaction is rapid and exothermic. At temperatures below 5°C the product is almost exclusively the alcohol. At 25—30°C the glycol predominates. Such synthesis also... 

Metals and Metal Derivatives, Silane reacts with alkah metals dissolved in various solvents, forming as the chief product the silyl derivative of the metal, potassium being the most commonly studied, eg, KSiH [13812-63-OJ (27—30). When 1,2-dimethoxyethane or bis(2-methoxyethyl)ether are used as solvents, two competing reactions occur, where M is an alkah metal. 

Using hexamethylphosphoramide as the solvent, only the second reaction occurs. Disilane also reacts with potassium in 1,2-dimethoxyethane to form KS1H3, although S1H4 and nonvolatile polysHanes are also produced (28,31). Pure crystalline KSiH prepared from SiH and potassium in 1,2-dimethoxyethane has been obtained by slow evaporation of the solvent. WhenHquid ammonia is used as the solvent, only a small fraction of SiH is converted into metal salt most of the SiH undergoes ammonolysis (32). 

DisHane undergoes disproportionation in 1,2-dimethoxyethane, forming SiH and a soHd material, [bpl]SiH2[bpr], when an alkah metal salt, eg, KH or LiCl, is present (33,34). 

Ethylene glycol dimethyl ether (monoglyme) [110-71-4] M 90.1. See 1,2-dimethoxyethane on... 

Commercial 1,2-dimethoxyethane, zur Synthese quality, was purchased from E. Merck, Darmstadt. 

Anhydrous lithium perchlorate (60 g.) obtained from Ventron Corporation was placed in a 500-ml. flask under dry nitrogen, and 85 ml. of anhydrous 1,2-dimethoxyethane was added. The mixture became... 

Although not so generally applicable for the preparation of dicyclopentadienyl metal compounds as the sodium cyclopenta-dienide method, the amine procedure represents the simplest preparation of ferrocene. The amine procedure can also be employed for dicyclopentadienylnickel (about 80% yield), using nickel bromide obtained by the action of bromine on nickel metal powder and 1,2-dimethoxyethane as the solvent. The method of preparation given here is a modified version of that originally described. ... 

An interesting variant in which nucleophilic aromatic substitution is carried out on the crown nucleus rather than using the crown as nucleophile was reported by Haines . In this approach, hexafluorobenzene was stirred in 1,2-dimethoxyethane at room temperature with pentaethylene glycol and sodium hydride. A double nucleophilic aromatic substitution occurred affording 2, 3, 4 ,5 -tetrafluorobenzo-15-crown-5 as an oil in 38% yield. The reaction is illustrated below. 

The dry tosylhydrazone (20 g, 45.5 mmol) is dissolved in 750 ml of 1,2-dimethoxyethane (freshly distilled from lithium aluminum hydride) in a flame-dried 1 liter round bottom flask fitted with a 240 ml addition funnel, a drierite tube and a magnetic stirrer. A 2.05 M ether solution of methyllithium (130 ml, Alfa Inorganics, Inc.—Caution to avoid the mineral oil impurity the methyllithium solution is decanted from a cold solution which contains a precipitate) is placed in the dropping funnel and added over a 60 min period. The temperature of the reaction mixture increases to ca. 35° during the addition however, no cooling precautions are required. The highly colored reaction mixture is stirred for 7 hr and then poured into 1.5 liters of ice water. The flocculent precipitate is digested for 12 hr at room temperature to speed the filtration. After filtration the filter cake is washed with 500 ml water and dried under vacuum at 50° for several hr. The androsta-5,16-dien-3l5-ol is obtained in ca. 70% yield after recrystallization from methanol mp 138-139°. 

Tnmethyl(trifluororaethyl)tin can also be prepared via in situ formation and capture of tnfluorometbide by trimethyltin chlonde [13, 14] (equation 9) This tin analogue has been used as a precursor for difluorocarbene either by thermal decomposition or by reaction with sodium iodide m 1,2-dimethoxyethane This carbene generation procedure has been used to study difluorocarbene selectivity with steroidal olefins [75] (equation 10). 

The smaller c/oio-dianions (n = 6, 7, 8) can then be obtained (in smaller yield) by the oxidative (air) degradation of BgHg " salts in the presence of EtOH, thf or 1,2-dimethoxyethane. 

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