ethyl 7-bromo-3-hydroxynaphthalene-2-carboxylate

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A solution of 81 g (0.3 mol) of 7-bromo-3-hydroxy-2-naphthoic acid in 600 ml dried EtOH and 60 ml conc. sulfuric acid was heated at reflux for 16 hours. The mixture was cooled to room temperature and treated with water (4000 ml) and neutralised with NaHCO3. The solid was separated by filtration and dried in a drying chamber afforded 75.3 g (85%) of the titled compound. at reflux for 16 hours The solid was separated by filtration dried in a drying chamber

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 3.8 g (12.88 mmol) ethyl 7-bromo-3-hydroxynaphthalen-2-carboxylate, 3.0 g (15.5 mmol) 1-(tert.-butoxycarbonylamino)-3-chloropropane (prepared according to Helv. Chim. Acta 76 (1993), 1644), 2.0 g (14.5 mmol) potassium carbonate, and a catalytic amount of potassium iodide in 20 ml dry DMF was stirred at 90° C. for 6 h. It was poured into water, extracted three times with ethyl acetate, and the combined organic layers were washed three times with water, dried over sodium sulfate, and concentrated in vacuo. The intermediate was purified by chromatography on silica gel with toluene/acetone 9:1 to give 5.8 g (100%) of a yellow oil, which solidified rapidly upon standing. extracted three times with ethyl acetate the combined organic layers were washed three times with water dried over sodium sulfate concentrated in vacuo The intermediate was purified by chromatography on silica gel with toluene/acetone 9:1