Chlorohydrins trimethylene chlorohydrin

The trimethylene chlorobromide used boiled at 142-1470. It may be prepared in 75-85 per cent yields from trimethylene chlorohydrin (p. 112) by the general method for the preparation of alkyl bromides described in Org. Syn. 1,1. 

J-Chloropropionic acid has been prepared by the hydrolysis of ethylene cyanohydrin with hydrochloric acid,1 and by the oxidation of /S-chloropropionaldehyde2 or of trimethylene chlorohydrin 3 by nitric acid. 

Larger runs may be carried out without lowering the yield. When a run of four times that described was made, the time of adding the trimethylene chlorohydrin was only doubled. 

To obtain the trimethylene chlorohydrin, the distillate from this operation is heated for about one hour on a steam bath in order to drive out most of the excess hydrogen chloride. The distillate is then fractionated under reduced pressure (Note 3) in a modified Claisen flask (Org. Syn. 1, 40). The fractionating side arm should be 25 cm. in length. The fractions collected under 10 mm. are to 55°, 55-57°, 57-65°, 65-85°, 85-105°, residue. 

The material boiling above 65°/io mm. is chiefly trimethylene glycol and is used in a succeeding experiment. The final yield of trimethylene chlorohydrin (Note 5) boiling at 6o-64°/io mm. is 835-1000 g. from 1800 g. of trimethylene glycol (50-60 per cent of the theoretical amount), and 400-450 g. of trimethylene glycol is recovered. 

Trimethylene chlorohydrin cannot be distilled under atmospheric pressure without some decomposition. The fractionation can be carried out at ordinary pressures when the fractions collected are up to 1250, 125-158°, 158-164°, 164-190°, 190-210° and residue. This procedure is less desirable as some hydrogen chloride is evolved and the product turns dark on standing. 

The chlorohydrin contains a very small amount (less than 0.5 per cent) of water-insoluble material, which is probably trimethylene chloride and di- y-chloropropy 1 ether. 

The general plan of Organic Syntheses has been discussed in the prefaces of the previous volumes. In this volume are published two distinctly different methods of preparation for each of two compounds. The directions for producing /3-chloro-propionic acid first from acrolein and second from trimethylene chlorohydrin, and for producing trimethylacetic acid first from terJ-butyl chloride and second from pinacolone, have been included. This has been deemed advisable since in some countries one raw material is more readily available than the other. 

Trimethylcyclohex-2-en-l-one, i93 1,2,2-Trimethyl- 1,3-cyclopentanedicarboxylic acid, c4 Trimethylene chlorobromine, b307 Trimethylene chlorohydrin, c231 Trimethylenediamine, pi 90... 

Trimethylene chlorobromide, b257 Trimethylene chlorohydrin, c214 Trimethylenediamine, pi 93 Trimethylene dibromide, d93... 

Trimethylene chlorohydrin has been prepared from tri-methylenc glycol by the action of dry hydrogen chloride... 

SYNS 3-CHLORPROPAN-l-OL I-PROPANOL, 3-CHLORO- TRIMETHYLENE CHLOROHYDRIN... 

Trimethylene oxide and its homologs are prepared from the corresponding trimethylene chlorohydrins and alkali. The yield is higher when y-chloropropyl acetate is substituted for the chlorohydrin (44% vs. 

Phosphorus tribromide (271 g., 1.0 mole) is stirred and cooled in an ice bath while 189 g. (2.0 moles) of trimethylene chlorohydrin [Org. Syntheses Coll. Vol. 1, 533 (1941)] is added dropwise over a 2-hour period. The reaction mixture is protected from atmospheric moisture by a calcitim chloride tube during this and the subsequent operation. The mixture is then heated on a water bath and stirred for 10 hours, after which it is cooled and poured into 11. of cold water. The organic layer is washed with 10% aqueous sodium carbonate... 

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