Glycols diethylene glycol dimethyl ether

A solution of cholest-4-en-3-one (139), 1 g, in diethylene glycol dimethyl ether (20 ml) is treated for 1 hr with a large excess of diborane at room temperature under nitrogen and then left for a further 40 min. Acetic anhydride (10 ml) is added and the solution refluxed for 1 hr. The mixture is concentrated to a small volume, diluted with water and extracted with ether. The extracts are washed with 10% sodium hydroxide solution, then with water and dried over sodium sulfate. Removal of the solvent leaves a brown oil (1.06 g) which is purified by chromatography on alumina (activity I). Hexane elutes the title compound (141), 0.68 g mp 76-77°. Successive crystallization from acetone-methanol yields material mp 78-79°, [a]p 66°. 

Ethynylation of 3j -hydroxy-16a-methyl-5a-androstan-17-one in a mixture of diethylene glycol dimethyl ether and diethylene glycol monoethyl ether in the presence of potassium hydroxide produces two isomeric 17-ethynyl derivatives. This result is not unexpected since molecular models suggest that the steric influence of the 13/ -methyl group is nearly offset by the 16a-methyl group. The presence of a 16a-acetoxy group in the estrone series also leads to the formation of epimeric 17-ethynyl compounds (61) and (62) on reaction with acetylenedimagnesium bromide. 

A mixture of 8.5 g (0.03 mol) of 6-chloro-4-amino-benzene-1,3-disuifonamide, 4.0 g (0.033 mol) of 2,5-endomethylene-A -tetrahydrobenzaldehyde and 25 cc of diethylene-glycol-dimethyl ether was heated for 2 hours at 100°C. During this time the major portion of the initialiy undissolved crystals went into solution thereafter, the reaction mixture was allowed to stand for 14 hours at room temperature, during which the remaining undissolved crystals also went into solution. The reddish, clear solution thus obtained was admixed... 

A mixture consisting of 22.7 g potassium o-bromobenzoate, 16.6 g 2,6-dichloro-3-methvlani-line, 12 ml N-ethylmorpholine, 60 ml diethylene glycol dimethyl ether, and 1.0 g anhydrous cupric bromide is heated in a nitrogen atmosphere at 145 C to 155°C for 2 hours. The reaction mixture is diluted with 60 ml diethylene glycol dimethyl ether and acidified with 25 ml concentrated hydrochloric acid. The acidic mixture is diluted with 100 ml of water and the liquid phase decanted from the insoluble oil. The insoluble oil is stirred with methanol and the crystalline N-(2,6-dichloro-3-methylphenyl)anthranilic acid which separates is collected and washed with methanol. The product, after recrystallization from acetone-water mixture melts at 248 C to 250°C. 

Ketene di(2-melhoxyethyl) acetal has been obtained by the present method with the use of diethylene glycol dimethyl ether as solvent.3 Other methods for the preparation of ketene acetals include the dehydrohalogenation of a halo acetal with potassium t-butoxide 4 and the reaction of an a-bromo orthoester with metallic sodium.5... 

Largest peak in the mass spectrum of propylene glycol ethers CH3OCH2CH2— (diethylene glycol dimethyl ether)... 

The UV spectra for the azide in a diethylene glycol dimethyl ether solution and for the styrene resin film with 1.0 micron thickness are shown in Figure 5. The azide has an intense absorption at around 248 nm (molar extinction coefficient at 248 nm = 3.0xl04 1/M cm). The syrene resin used as matrix polymer exhibits a significant transparency at 248 nm (70%). 

Figure 5. UV spectra for (a) 4,4 -diazidodiphenyl methane in a diethylene glycol dimethyl ether (7.2xl0 5 mole/1) and (b) poly(styrene-co-maleic acid half ester) (1.0 micron film thickness).

C6H1403 DIETHYLENE GLYCOL DIMETHYL ETHER 6.517E-04 604.00 -0.7143 203.15 573.80 1.060E-03 0.942... 

If an internal olefin is treated similarly and the resulting branched trialkylborane heated at about 160° in diethylene glycol dimethyl ether, the molecule is rearranged and finally the terminal trialkylborane is produced. The isomerization of the organoborane proceeds through a series of eliminations to regenerate olefin and dialkylborane, followed by... 

Borane prepared by adding aluminum chloride to a solution of sodium borohydride in diethylene glycol dimethyl ether (diglyme) reduced aliphatic and aromatic esters to alcohols in quantitative yields in 3 hours at 25° using a 100% excess, or in 1 hour at 75° using a 25% excess of lithium borohydride over 2 mol of the hydride per mol of the ester [738] Procedure 20, p. 209). 

Cyclocondensation of 2-amino-5-nitro-3-pyridinecarboxamide with 4-hydroxybenzaldehyde in the presence of ZnCl2 in refluxing diethylene glycol dimethyl ether gave the pyridopyrimidine 351 <1994MIP2056742>. Reaction of ethyl 2-(l-ethoxyethylidene)amino-4,5,6-trisubstituted-3-pyridinecarboxylate with A -(2-aminoethyl)morpholine in the presence of HCl gave the polysubstituted pyridopyrimidin-4(3/7)-one 352 <1997W09719946>. 

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