Water → 5-Bromoquinoline-8-carboxylic acid

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of potassium permanganate (18.2 g, 115.5 mmol, 2 equiv) in H2O (200 mL) was added to a hot (110° C.) solution of 5-bromo-8-methyl-quinoline (Step 159.4) (12.8 g, 57.7 mmol) in pyridine (120 mL). The reaction mixture was stirred for 10 min at 110° C. and filtered while hot. The residue in the filter was washed with H2O and pyridine. The filtrate was concentrated to remove pyridine, diluted with Et2O and basified by addition of a 2 N aqueous solution of NaOH (20 mL). The aqueous layer was separated and made acidic (pH 3) by addition of a 2 N aqueous solution of HCl. The resulting precipitate was collected by vacuum filtration to provide 1.45 g of the title compound as a green solid: ESI-MS: 251.9/253.9 [M+H]+; tR=3.56 min (System 1).

Herkunft & Nachweise