PROCESS FOR PREPARING DIBENZO (B,E) PURANQ (3,2-B)-1-BENZOPYRILIUM SALTS Russian patent published in 1997 - IPC

FIELD: paint industry. SUBSTANCE: claimed invention describes preparation of compounds of formula (I) wherein X is 0; R₁ is hydrogen atom; R₂, R₃, R₄ is hydrogen or halogen atom; C₁- C₆ is alkyl or C₁- C₆ alkoxy or nitro; R₅, R₆, R₇ are hydrogen atom or C₁- C₆ alkyl having high fluorescent characteristics and useful for dyeing anion modified fibers and as fluorescent dyes, 2-R₅-5, 5-R₆, R₇-cyclohexane-1,3-diones are reacted with substituted or unsubstituted salicylic aldehydes in the presence of chloric acid and triethylorthoformate. Data: N; R₁, R₂, R₃, R₄, R₅, R₆, R₇. Yield (%): mp(C) 1a; H, H, H, H, H, CH₃, CH₃: 546; 294-297; 1b; H, OCH₃, H, H, H, CH₃, CH₃; 58.5; 303-305; 1c, H, NO₂, H, H, H, CH₃, , CH₃; 42.0; 312-315; 1d; H, Br, H, H, H, CH₃, , CH₃ 71.3; 281-284; 1e; CH₃, H, H, H, CH₃, , CH₃; 47.7; 272-273; 1f; H, H, CH₃, H, H, CH₃, , CH₃; 52.3; 277-278; 1g; H, Br, H, Br, H, CH₃, , CH₃; 68.1; 314-315; 1h; H, Br, OCH₃, Br, H, CH₃, , CH₃; 55.3; 300-302; 1i; H, CH₃, , NO₃, H, H, CH₃, , CH₃; 46.7; 297-299. EFFECT: more efficient preparation process. 1 tbl