GB1499139A - Process for the extraction of zinc values - Google Patents

Abstract

1499139 8-Hydroxy quinolines GENERAL MILLS CHEMICALS Inc 4 March 1975 [4 March 1974] 8932/75 Heading C2C [Also in Division C1] Substituted 8-hydroxy quinolines useful in the solvent extraction of zinc values from aqueous solutions of the formula wherein X is H, Cl, Br or R 4 ; R 4 is a branched chain alkyl or alkenyl radical containing 3-22 C, the rotal C in the substituents in the 5 and 7 positions being 8-25 and R 1 , R 2 and R 3 are H or alkyl groups of 1-4 C. R is preferably an alkenyl group of 12 or more 12 C atoms and X is preferably Cl or Br. The 7-alkenyl substituted compounds may be prepared by reacting 5-halo- 8-hydroxy quinoline with an alkenyl chloride in the presence of sodium hydroxide and dimethyl sulphoxide with subsequent heating. 7-Alkyl substituted compounds may be prepared by reacting 8-hydroxy quinoline with an alkenyl chloride in the presence of sodium hydroxide dimethyl sulphoxide. The product may then be hydrogenated and chlorinated or brominated. The compounds R 1 , R 2 or R 3 are alkyl and are desirably prepared by reacting 2-amino-4-halophenol with an alpha, beta unsaturated aldehyde in the presence of 2-nitro 4-halophenol, ferrous sulphate and sulphuric acid. Such compounds may then be reacted as above with an alkenyl chloride. The examples relate to the preparation of substituted 8-hydroxy quinolines, in particular (A) 5-chloro-7-dodecenyl-; (B) 5-chloro-7-dodecyl-; (C) 5-bromo-7-dodecyl-; (D) and (E) 5-chloro-7-C 12 H 23 -; (F) 5- chloro - 7 - C 8 H 15 -; (G) 3-methyl-5-chloro-7- dodecenyl-; (H) 2-methyl-5-chloro-7-C 12 H 25 -; (I) 2-methyl-5-bromo-7-dodecyl- and (J) 4- methyl-5-chloro-7-C 12 H 25 -.