Diethylene glycol, from preparation

Figure 4.7 Differential pore size distribution curves of the polyfglycidyl methacrylate-co-diethylene glycol dimethacrylate) prepared by suspension polymerization at the temperatures (1) 90 and (2) 70 C initiated by (a) benzoyl peroxide and (b) 2,2-azo(bis-isobutyronitrile). (Reprinted from [383] with permission of the American Chemical Society).

The residue in the flask is either a solution or a suspension of the potassium salt of the acid derived from the ester in diethylene glycol. Add 10 ml. of water and 10 ml. of ethyl alcohol to the residue and shake until thoroughly mixed. Then add a drop or two of phenolphthalein and dilute sulphuric acid, dropwise, until just acid. Allow the mixture to stand for about 5 minutes and then Alter the potassium sulphate. Use the clear filtrate for the preparation of a sohd derivative or two of the acid (see Section 111,85,4). 

Diester/Ether Diol of Tetrabromophthalic Anhydride. This material [77098-07-8] is prepared from TBPA in a two-step reaction. First TBPA reacts with diethylene glycol to produce an acid ester. The acid ester and propylene oxide then react to give a diester. The final product, a triol having two primary and one secondary hydroxyl group, is used exclusively as a flame retardant for rigid polyurethane foam (53,54). 

A number of useful resins have been prepared from allyl compounds, i.e. derivatives of allyl alcohol CH2 = CH CH20H. One of these, diethylene glycol... 

Chen, J.-W. and Chen, L.-W., The kinetics of diethylene glycol formation from bishydroxyethyl terephthalate with antimony catalyst in the preparation of PET, J. Polym. Sci., Polym. Chem. Ed., 37, 1797-1803 (1999). 

An approach to this type of ring system that has been classified as a diazaindole is shown in Equation (74). Here 213 has been prepared in two steps from 5-bromopyrimidine. Heating this compound at reflux in diethylene glycol affords 214 in very poor yield <2003JME4702>. 

A distilled ethereal solution (300 ml.) containing approximately 0.96 mole of diazomethane (Note 1) is prepared from 22.5 g. of a 70% dispersion (15.8 g., 0.063 mole) of bis-(N-methyl-N-nitroso)terephthalamide (Note 2), 75 ml. of aqueous 30% sodium hydroxide, 55 ml. of diethylene glycol monoethyl ether, and 375 ml. of ether by the procedure described in an earlier volume of this series.5 The receiving flask containing the ethereal diazomethane is capped with a rubber stopper fitted with a drying tube containing potassium hydroxide pellets to protect the solution from atmospheric moisture. The concentration of diazomethane in this ether solution may be determined either by titration with ethereal benzoic acid (Note 3) or spectrophotometrically (Note 4). 

Fig. 4.3. GPC of a Polyazoester Prepared from AIBN and Diethylene Glycol...

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