N[C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([C:11]([O:13][CH3:14])=[O:12])[CH:10]=1)[C:5]([OH:7])=[O:6].Cl.N([O-])=O.[Na+].[I-:20].[K+]>O>[I:20][C:2]1[CH:3]=[C:4]([CH:8]=[C:9]([C:11]([O:13][CH3:14])=[O:12])[CH:10]=1)[C:5]([OH:7])=[O:6]
To an ice-cold, stirred solution of 3-amino-5-(methoxycarbonyl)benzoic acid (5.19 g, 26.59 mmol) in a 2 N hydrochloric acid (156 mL) was added a solution of sodium nitrite (1.84 g, 26.67 mmol) in water (10.8 mL). This mixture was then added dropwise to an ice-cold, stirred solution of potassium iodide (8.84 g, 53.25 mmol) in water (26.2 mL). After stirring for 35 min, the reaction mixture was diluted with water and extracted with ethyl acetate. The organic layer was washed with 5% aqueous sodium thiosulfate, and saturated sodium chloride, dried (sodium sulfate), and concentrated under reduced pressure. Purification by flash column chromatography (silica, 50:50:2 hexanes/ethyl acetate/acetic acid) afforded 3-iodo-5-(methoxycarbonyl)benzoic acid (4.48 g): 1H NMR (500 MHz, DMSO-d6): δ 13.49 (br s, 1H), 8.45-8.38 (m, 3H), 3.83 (s, 3H); ESI-MS (m/z): 305 [M+H]+.
Wird geladen…
