Sulfuric Acid → 6-iodo-3,4-dihydronaphthalen-1(2H)-one

Participants

Reaction Conditions

Reaction Steps

To a stirred clear solution of 6-amino-3,4-dihydronaphthalen-1(2H)-one (15 g, 93 mmol) in acetic acid (150 mL) and water (150 mL) was added sulfuric acid (5.5 mL, 101 mmol) dropwise at 0° C. A solution of sodium nitrite (12.90 g, 187 mmol) in water (100 mL) was then added dropwise over 40 min at the same temperature. The mixture was stirred at 0° C. for 10 min before being added to a stirred solution of sodium iodide (55.8 g, 372 mmol) in water (600 mL) slowly over 2 h at 0° C. The resulting brown suspension was stirred at 0° C. for 30 min and at room temperature for 1 h. The mixture was extracted with ethyl acetate (400 mL, 2×100 mL). The combined ethyl acetate extracts were washed with water (60 mL), saturated aqueous Na2S2O3 solution until the brown color disappeared, and saturated aqueous K3PO4 (60 mL) solution, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. Flash chromatography purification (330 g silica gel column, gradient elution from 5 to 15% ethyl acetate in hexanes) afforded 6-iodo-3,4-dihydronaphthalen-1(2H)-one (17.3 g, 63.6 mmol) as a solid. LC/MS M+1=273.

Provenance & Evidence