DE409345C - Process for the preparation of oxazolines - Google Patents

Description

Process for the preparation of oxazolines. For the production of oxazolines nian was previously dependent on the use of aliphatic bromamines or their substitution products, z. B. According to G abrie 1, 2-plienvloxazoli: din was obtained by dissolving Broinä thvlbenzamid: It has now been found that oxazolines or their derivatives and substitution products can also be obtained by starting from amino alcohols or their acidyl derivatives substituted on the sticks '' off. The result of the process is as simple as: \ @ 'asserabspalttin.g according to: your scheme: ( O # R means the residue of any organic acid, e.g. acetyl, e.g. substituted alkyl radical, such as methyl, carboxymethyl, chloromethyl, oxymethyl.

Various substances can be used as condensation agents strongly bind water, e.g. B. Thiony lchloriid, Carbony lchlorid or hydrogen chloride in ether. It is most convenient to work with thionyl chloride; it already works in the cold very quickly, and the oxazoline formed can either be obtained as hydrochloric acid Salt by ether, carbon tetrachloride or the like directly .from the reaction liquid precipitate or, best of all, after removing most of the thionyl chloride and Decomposition with aqueous alkali, in the known way: separate and clean.

The oxazolines are said to be used for pharmaceutical purposes.

Example i.

0,. \ 7-D.ibenzoylaminopropylene glycol (Ber. Dd chem. Ges. 5d., P. 950 [192i]) is poured over i4 times the weight of dry ether, whereupon hydrogen chloride gas is introduced with cooling until it is saturated After the initial solution falls: soon the hydrochloric acid salt of 2-phenyl-5-benzoyloxymethyloxazoline has a melting point of 130 °. The free oxazoline melts at 52 °. It forms colorless needles or six-sided prisms. It is under greatly reduced pressure It can be easily distilled in all organic solvents except petroleum ether and water .

C6H- # CO - C142 - CH (OCO C, H.) - CH, - 1H2, HCl (Ber. Dd chem. Ges. 54., p.950 [1921]), converted. Examples. Chloroxypropyllaurylamide Cl - CHF - CH (OH) - CH = # i'H # CO # 611H =., Is left to stand for a short time at normal temperature with 3 times the amount of thionylchloride. After the addition of ether, the hydrochloric acid 2-undecyl-5-chloromethyl oxazoline soon crystallizes. The colorless salt melts at 75 to 10 °, it dissolves easily in chloroform, but only unchanged in a very little water; more water cleaves it with an oily separation of the free oxazoline. If you stand for a little longer with V4Tasser or with hydrochloric acid, the salt of a-lauroyloxy-ß-oxypropyl-y-ainine 611H-, - CO - O - CH = # CH (OH) - CH_ - HCI (no sharp melting point) above.

The chloroxypropyllaurylamide, which is used as the starting material, arises from the treatment of 2-phenyl-5-chloromethyloxazolidine (Ber. Dd chern. Ges. 54, p. 1645 [1921]) with lauric acid chloride. The intermediate product obtained is 2-phenyl-3-lauroyl-5-chlorine-ethyloxazolidine, (but it cannot be deposited)> smokes. The procedure is then, for example, as follows: The solution of 10 g of phenylchloromethlyloxazolidine in a few cubic centimeters becomes anhydrous chloroform mixed with 5 g of pyridine and substantially pure lauric acid chloride, stored for 1 to 2 days, then evaporated in vacuo and the oily residue immediately shaken with 25% hydrochloric acid for 1 hour, the benzaldehyde being split off from the intermediate product to, as soon the Chloroxypropylamid looking for 58 °. example 3 fails. Colorless crystals of carbon tetrachloride with petroleum ether of melting.. in all organic solvents slightly soluble, as in carbon tetrachloride in petroleum ether very difficult Icslich.

6 gy-benzamido-β-oxybutyrate (cf. Zeitschr. F. Physiol. Chem. 131 p. 9) are dissolved in 20 cc of thionyl chloride. After 1 hour, the hydrochloric acid salt of 2-phenyl-5-carbethoxymethyloxazoline is removed by ether felled in good yield. It forms colorless and odorless needles with a melting point of 118 to 19 °, soluble in chloroform and similar organic solvents, also in water, but not in petroleum ether. The salt is quickly changed by hydrochloric acid with ring bursting.

The ethyl benzamidooxybutyrate used as the starting material is made from chloroxypropylbenzamide (Ber. d. d. chem. Ges. 54, p. 16152 [1921]) with Potassium cyanide in alcoholic-aqueous solution when boiling for 3 hours over the cyano compound CEH, CO - NH - CH @ - CH (OH) - CH, - C \ (needles or oblong plates of the Schnip. 128 up to 129 °) by subsequent alcoholysis of the cyano group with alcoholic hydrogen chloride and subsequent treatment with water. The ester obtained in this way is color- and odorless. It melts at 99 to 100 ° and dissolves well in alcohol, acetone, - poor benzene, hot ethyl acetate, very heavy in petroleum ether.

Claims (1)

PATENT CLAIM: Process for the preparation of oxazolines, thereby characterized in that one has N-acidyl derivatives of amino alcohols or their substitution products treated with strong dehydrating agents.