4-(BENZIMIDAZOLYL-2')-QUINOLINE DERIVATIVES AS INHIBITORS OF STEEL CORROSION IN ACID MEDIA Russian patent published in 1998 - IPC

FIELD: organic chemistry. SUBSTANCE: invention relates to heterocyclic compounds, in part, derivatives of 4-(benzimidazolyl-2')-quinoline of the formula: where: 1) R - H₂O;; 2) (C₂H₅)₂SO₄. Compound (2) is synthesized by reaction of 2-(quinolyl-4)-benzimidazole hydrate with diethylsulfate in acetone medium at the room temperature. Compound (1) is synthesized by condensation of o-phenylenediamine with 4-quinolinecarboxylic acid in the presence of pyrophosphoric acid. The yield, %; m. p., C; empirical formula: 1) 72; 136; C₁₆H₁₁N₃•H₂O;; 2) 54; 192-193; C₂₀H₂₁N₃SO₄.. At concentration 0.05-0.8 g/l inhibitory activity of synthesized compounds is 90% at 30-90 C. Chemical and mechanical stability of polystyrene composition is improved. EFFECT: improved method of synthesis, increased yield. 4 tbl