Über die Wirkung von schwefliger Säure und ihren Salzen auf Chinolin‐Derivate. (Vorläufige Mitteilung.)

The Reactions Of 8-Quinolinol

“…Sodium bisulfite or a solution of sulfur dioxide heated for many hours with oxine gives only a crystalline addition compound of sulfur dioxide that readily loses the sulfur dioxide (302). Direct chlorination with one mole of chlorine per mole of oxine gives only a poor yield of 5-chloro-8-quinolinol together with some 5,7-dichloro derivative and unreacted 8-quinolinol (34,123), but the yield can be increased to 74 per cent by the addition of a little antimony trichloride (250).…”

“…Yields from the Skraup reaction of o-aminophenol, o-nitrophenol, glycerol, and sulfuric acid are poor (132, 266, 292), although better than 90 per cent yields can be obtained from modern modifications in which most of the sulfuric acid is replaced by acetic acid (60) and ferrous sulfate-boric acid additions are used (134, 170). The fusion of 8quinolinesulfonic acid, obtained by sulfonating quinoline, with sodium hydroxide gives 90 per cent yields (112,164,302). Heating 8-chloroquinoline with sodium hydroxide under pressure produces an 87 per cent yield (291), and almost quantitative yields of 8-quinolinol are obtained when 8-aminoquinoline is heated with sulfuric acid in an autoclave (84).…”

Bacterial Aromatic Sulfonates - A Bucherer Reaction in Nature?

“…As do many aliphatic and aromatic amines [28], also quinoline reacts with gaseous as well as with liquid SO 2 to give a 1:1 solid yellow addition compound melting at 53°C [29,30]. Combustion analyses suggested also here the addition of SO 2 (C 9 H 7 O.SO 2 ) [31]. 80-81°C.…”

“…80-81°C. An explanation could be that under mild conditions (warming in a water bath [31]) a sulfite ester is obtained while under more drastic ones (7 hours in an autoclave at 150°C [32]) the quinoline analog of 2a and subsequently aminoquinoline is formed. By both procedures yellow crystals (mp.…”