PREPARATION OF ETHERS BASED ON 5-CHLOROMETHYL-8-HYDROXYQUINOLINOL HYDROCHLORIDE

L. I. ARISTOV, G. G. SEREBRYANSKAYA

(Presented by the Scientific-Methodological Seminar of the Faculty of Chemical Technology)

As Burckhalter [1] showed, under the conditions of the chloromethylation reaction, 8-hydroxyquinoline forms, in good yield, the hydrochloride of a chloromethyl derivative. We used this compound for the synthesis of ether-type compounds with unsaturated bonds, namely a simple allyl ether and an ester of methacrylic acid. The substances obtained are capable of forming inner-complex compounds with salts of heavy metals that possess some solubility in tetrahydrofuran, dioxane, and dimethylformamide.

As established by preliminary experiments, the methacrylic acid ester is capable of polymerizing with peroxide initiators and also of giving copolymers with styrene and with methyl methacrylate.

The simple allyl ether of 5-methylene-8-hydroxyquinoline does not polymerize with peroxide initiators, but forms copolymers with methyl methacrylate and with styrene under conditions of bulk and emulsion polymerization. The detailed properties of the copolymers are being studied.

Experimental Part

Allyl ether of 5-methylene-8-hydroxyquinoline. To 10.75 g (0.05 mol) of 5-chloromethyl-8-hydroxyquinoline hydrochloride is added 4.2 g (0.05 mol) of sodium bicarbonate; the mixture is stirred and introduced into a flask containing 50 ml of ethyl acetate. To the contents is added 5.4 g (0.1 mol) of allyl alcohol, and the entire reaction mass is heated under a reflux condenser for 2 hours. After cooling, the reaction mass is filtered. The resulting yellow precipitate is transferred to a beaker and dissolved in water. From the aqueous solution the ether is isolated by adding a weak ammonia solution to neutral reaction. After recrystallization from petroleum ether, 6 g of the substance is obtained in the form of white needles with a melting point of 81–82°C. An attempt to distill the ether at atmospheric pressure led to decomposition of the substance with distillation of allyl alcohol. Found, %: N—6.72%; C₁₃H₁₃NO₂, calculated, %: N—6.51; unsaturation by Hanus—found: 120.5, calculated 119.

8-Hydroxy-5-methylenequinolyl ester of methacrylic acid. To 10.75 g (0.05 mol) of 5-chloromethylquinolinol hydrochloride is added 12.4 g (0.1 mol) of the potassium salt of methacrylic acid ...

acid, the contents are stirred and introduced into a flask containing 100 ml of ethyl acetate. The reaction mixture is heated under reflux for 2 hours and rapidly filtered. From the filtrate the ether precipitates in the form of white flakes, which are filtered off, washed with water, and dried. After two recrystallizations from ethyl acetate, 8 g of substance with m.p. 128°C was obtained. The ether is soluble in ethyl acetate, alcohol, dioxane, and tetrahydrofuran.

Found, %: C — 68.79; H — 5.28; N — 5.88%, \(C_{14}H_{13}NO_3\); calculated, %: C — 69.13; H — 5.35; N — 5.76.

Conclusions

Ethers based on 5-chloromethyl-8-hydroxyquinoline were synthesized: a simple ether—allyl ether—and a complex ether—of methacrylic acid.

Literature

1. J. H. Burckhalter, R. I. Leib, J. Org. Chem., 26, 4078, 1961.