Diethyl ether, reaction

The p-tolylphosphine complex is prepared in a similar manner, except that its greater solubility in THF and diethyl ether precludes precipitation with diethyl ether. The product is isolated by removing the THF/diethyl ether reaction solvent under vacuum and extracting the residue with toluene (dried by distillation from sodium). The toluene extracts are filtered and diluted with an equal volume of hexane (dried by distillation from sodium). Upon slow cooling, fine red needles are deposited. 

In the work-up of the diethyl ether reaction, the solvent is removed (in a hood) under a stream of nitrogen. Then the ether-free aqueous dispersion is mixed with 10 ml of a 5 mM EDTA solution to bind the calcium ions. Without the latter treatment, the calcium salt of the phosphatidic acid cannot be recovered (easily) from the reaction mixture. Thus, subsequent to the EDTA treatment, the sample is mixed with sufficient chloroform and methanol to make a mixture of chloroform-methanol-water (1 2 0.8, v/v). Then 0.5 volume chloroform and 0.5 volume water are added, and the mixture is vigorously shaken for 1 min and then allowed to separate into two phases. The upper, water-rich phase contains free nitrogen base—in this case, choline. It can be analyzed by the techniques described earlier. 

These products are obtained in good yields either by treating the sulfamoyl chloride with liquid ammonia or by refluxing it with the appropriate amine in an inert solvent such as chloroform, benzene, or diethyl ether. Reactions with aliphatic amines are usually complete in 12 hours those with aromatic amines require up to 24 hours. Two typical procedures are given. 

An interesting solvent effect (Scheme 3) was observed by Okhlobystin [96] and later by Brown [97]. In both cases the use of THF rather than diethyl ether allowed the complete alkylation of a group XIII substrate, whereas the diethyl ether reaction did not go to completion. 

The organometallic copper precursor is synthesized in two steps. First p-tolylcopper, Cu4(p-tolyl)4, is prepared from p-tolyllithium and copper(I) bromide in diethyl ether. Reaction between p-tolylcopper and a second equivalent of p-tolyllithium affords the cuprate [6-8]. (See equations 1-2.)... 

Anion (6) is best obtained in a redox condensation reaction [equation (b)] by reducing Ni(CO) with Na in the presence of anthracene and in boiling diethyl ether. Reaction in equation (b) is favored due to the removal of CO from the reaction mixture ... 

The inflammable solvents most frequently used for reaction media, extraction or recrystallisation are diethyl ether, petroleum ether (b.p. 40-60° and higher ranges), carbon disulphide, acetone, methyl and ethyl alcohols, di-Mo-propyl ether, benzene, and toluene. Special precautions must be taken in handling these (and other equivalent) solvents if the danger of Are is to be more or less completely eliminated. It is advisable to have, if possible, a special bench in the laboratory devoted entirely to the recovery or distillation of these solvents no flames are permitted on this bench. 

Di-alkyl ethers of ethylene glycol, ROCHjCHjOR. The dimethyl ether, b.p. 85°/760 mm., is miscible with water, is a good solvent for organic compounds, and is an excellent inert reaction medium. The diethyl ether (diethyl cdloaolve), b.p. 121-57760 mm., is partially miscible with water (21 per cent, at 20°). 

Diethyl ether may be prepared from ethyl alcohol by the sulphuric acid process. A mixture of alcohol and sulphuric acid in equimolecular proportions is heated to about 140° and alcohol is run in at the rate at which the ether produced distils from the reaction mixture. Ethyl hydrogen sulphate (or ethyl sulphuric acid) is first formed and this yields ether either by reacting directly with a molecule of alcohol or by the formation and alcoholysis of diethyl sulphate (I) ... 

The preparation of anhydrous diethyl ether (suitable for Grignard reactions, etc.) is described in Section 11,47,1. The precautions required in handling ether are given in Seetion 11,14. 

In contrast to alkylations with most of the alkyl halides, the reactions of anions with ethylene oxide in organic solvents such as diethyl ether and THE... 

It took 5-10 min before the reaction started this was visible by the appearance of turbidity of the diethyl ether and later by the appearance of a gloss on the pieces of lithium and a distinct increase in temperature. Care was taken that the temperature did not rise above -20°C (note 4). When the reaction had subsided, the addition of ethyl bromide was continued, now dropwise (note 5). The temperature was kept between -20 and -30 C (note 6). After the addition, which was carried out in 30-40 min, stirring was continued for about a further 1 h. The temperature was allowed to rise gradually to -10°C. When the gloss on the piece of lithium had disappeared, the solution was poured into another flask through... 

The flask was charged with 48 g of magnesium and 200 ml of dry diethyl ether. 1,2-Dibromoethane (4 ml) was added. After a few minutes a vigorous reaction started and the diethyl ether began to reflux. When this reaction had subsided, 500 ml of dry diethyl ether were added. Stirring was started and 1.0 mol of chlorocyclohexane (note 1) was added from the dropping funnel at a rate such that the diethyl ether gently refluxed (note 2). After this addition, which was carried out in 1 h, the flask was heated under reflux for a further 1 h. 

The lithiation of allene can also be carried out with ethyllithium or butyl-lithium in diethyl ether (prepared from the alkyl bromides), using THF as a cosolvent. The salt suspension which is initially present when the solution of alkyllithium is cooled to -50°C or lower has disappeared almost completely when the reaction between allene and alkyllithium is finished. 

A mixture of 0.40 mol of propargyl chloride and 150ml of dry diethyl ether was cooled at -90°C (liquid nitrogen bath) and a solution of 0.40 mol of ethyl-lithium (note 1) in about 350 ml of diethyl ether (see Exp. 1) was added with vigorous stirring and occasional cooling (note 2). The temperature of the reaction mixture was kept between -70 and -90°C. The formation of the lithium derivative proceeded almost instantaneously, so that the solution obtained could be used directly after the addition of the ethyl 1ithium, which was carried out in 15-20 min. This lithium acetylide solution is very unstable and must be kept below -60°C. 

To a solution of 0.30 mol of ethyllithium (note 1) in about 270 ml of diethyl ether (see Chapter II, Exp. 1) v/as added 0.30 mol of methoxyallene at -20°C (see Chapter IV, Exp. 4) at a rate such that the temperature could be kept between -15 and -2Q°C. Fifteen minutes later a mixture of 0.27 mol of >z-butyl bromide and 100 ml of pure, dry HMPT ivas added in 5 min with efficient cooling, so that the temperature of the reaction mixture remained below 0°C. The cooling bath was then removed and the temperature was allowed to rise. After 4 h the brown reaction mixture was poured into 200 ml of ice-water. The aqueous layer was extracted twice with diethyl ether. The combined solutions were washed with concentrated ammonium chloride solution (which had been made slightly alkaline by addition of a few millilitres of aqueous ammonia, note 2) and dried over potassium carbonate. After addition of a small amount (2-5 ml) of... 

A solution of 0.60 mol of ethyllithium (note 1) in about 400 ml of diethyl ether (see Chapter II, Exp. 1) was added in 30 min to a mixture of 0.25 mol of 1,4-diethoxy-2-butyne (see Chapter VIII-6, Exp. 8) and 100 ml of dry diethyl ether. The temperature of the reaction mixture was kept between -40 and -45°C. Fifteen minutes after the addition had been completed, 0.5 mol of methyl iodide was added at -40 C, then 100 ml of dry HMPT (for the purification see ref. 1) were added dropwise in 15 min while keeping the temperature at about -40°C. Thirty minutes after this addition the cooling bath was removed, the temperature was allowed to rise and stirring was continued for 3 h. The mixture was... 

Note 1. If commercial BuLi in hexane is used with diethyl ether or THF as cosolvent, a dark brown reaction mixture is formed, from which the desired product can be isolated in lower yields. 

The dilithiation can also be carried out with butyllithium in a 1 1 mixture of hexane and THF at -20°C (reaction time about 45 min). Subsequent alkylation is much faster than in diethyl ether. 

Under similar conditions (diethyl ether or THF as solvent) the reaction of lithium alkynylides with methanesulfonyl chloride (CH35O2CI) gave the corresponding alkynyl sulfones in low to moderate yields. 

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