Epichlorohydrin and Epibromohydrin

The prescribed amoimt of water should be used more water causes frothing. The reaction is not exothermic. 

Epichlorohydrin boils at 30-32°/ro mm., epibromohydrin at 6i-62°/5o mm. Both these liquids are quite volatile with water vapor under reduced pressure. 

Epichlorohydrin 1 and epibromohydrin have been prepared by treatment of glycerol dichloro- and dibromohydrins with 

In a 2-1. three-necked flask fitted with a mercury-sealed stirrer, reflux condenser, and dropping funnel is placed 500 cc. of absolute ethyl alcohol (Note 1), and 23 g. (1 gram atom) of cleanly cut sodium is added in portions. When the sodium has dissolved the solution is cooled to 6o°, and 146 g. (1 mole) of ethyl oxalate (Org. Syn. Coll. Vol. 1, 256) (Note 2) is added in a rapid stream through the funnel with vigorous stirring. This is washed down with a small quantity of absolute alcohol, and is followed immediately by the addition of 175 g. (1.06 moles) of ethyl phenylace-tate (Org. Syn. Coll. Vol. 1, 265) (Note 2). Stirring is discontinued at once, the reaction flask is lowered from the stirrer, and a 2-1. beaker is made ready. Within four to six minutes after the ethyl phenylacetate has been added crystallization sets in. The contents of the flask are transferred immediately to the beaker at the first sign of crystallization, which is nearly instantaneous. 

The nearly solid paste of the sodium derivative is allowed to cool to room temperature and then stirred thoroughly with 800 cc. of dry ether. The solid is collected by suction and washed repeatedly with dry ether. The phenyloxaloacetic ester is liberated from the sodium salt with dilute sulfuric add (29 cc. 

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Santodonato, J., et al. (1980) Investigation of Selected Potential Environmental Contaminants Epichlorohydrin and Epibromohydrin. US EPA-560/11-80-006. 

Santodonato, J., S. S. Lande, P. H. Howard, D. Orzel, and D. Bogy. 1980. Investigation of selected potential environmental contaminants Epichlorohydrin and epibromohydrin, U.S. Environmental Protection Agency. EPA-560/11 — 80-006. 

The early literature of epoxide chemistry contains several accounts of the reaction of hydrogen cyanide with epichlorohydrin, 11-1T1 epibromohydrin,10 ethyl glycidyl ether,J- and related substance Attack by the nucleophilic aperies, CN- ion in this case, occurs uniquely at the site furthest from the polar atom,. e. at the terminal epoxidi-carbon atom (Eq. 787), An important contribution was made by... 

B) Epibromohydrin.—In a 5-I. round-bottomed flask, 2140 g. (1000 cc., 9.8 moles) of glycerol a ,t-dibromohydrin (Org. Syn. 14, 42) is suspended in 1.5 1. of water, and 400 g. of technical, powdered calcium hydroxide (88 per cent) is added gradually, with shaking, in the course of about fifteen minutes. A further quantity of 400 g. of calcium hydroxide (total, 10 moles) is added at once, and the epibromohydrin is distilled at reduced pressure in the manner described for epichlorohydrin (Note 2). The combined lower layers from two such distillations (about 750 cc.) are dried over anhydrous sodium sulfate and fractionated at atmospheric or reduced pressxue. The yield of epibromohydrin, b.p. 134-136° or 6i-62°/5o mm., is 1130-1200 g. (84-89 per cent of the theoretical amount). 

Epibromohydrins and epichlorohydrins can be used as alternatives for 1,2-dihalides. The reaction of these compounds with suitable nucleophiles gives substituted hydroxymethylcyclop-ropanes (Table 8). Particular attention should be given to the use of 2-lithium bis(alkyl-... 

Glycidyl groups can be attached to PPE in a first step by increasing the amovmt of pendant hydroxyl groups, e.g., by a redistribution reaction. In a second step, these hydroxyl groups are allowed to react with epichlorohydrin [27]. Other reagents that have been claimed to be useful are epibromohydrin and glycidyl tosylate. 

Ng et al. described the use of less expensive and industrially far better available epichlorohydrine instead of the bromo derivative, but in the experience of the authors of this book the synthesis could not be reproduced in good yields. Another nucleophilic route to EDOT-CH2OH, very similar to the scheme in Figure 12.2, utilizes l-acetoxy-2,3-dibromopropane instead of epibromohydrin (Figure 12.3). Although formation of the undesirable isomer ProDOT-OH is omitted, the synthesis suffers from low yields (about 25%) in the nucleophilic substitution step. ... 

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