反应详情

Sodium metal (29 mg, 1.26 mmol) was added to 1.3 mL of ethanol and stirred until homogeneous. of 1-[6-(4-Bromo-phenoxy)-pyridin-3-yl]-pyrrolidine-2,2-dicarboxylic acid diethyl ester (0.20 g, 0.42 mmol) was added, followed by urea (75 mg, 1.26 mmol) and the mixture was stirred for 5 minutes at 80° C. The mixture was cooled to ambient temperature, acidified with 1M hydrochloric acid and extracted 3× with ethyl acetate. The combined organic phases were dried over sodium sulphate, filtered and concentrated in vacuo. The residue was purified by silica gel chromatography (3:1 hexane-ethyl acetate), affording 28 mg of 1-[6-(4-Bromo-phenoxy)-pyridin-3-yl]-1,7,9-triaza-spiro[4.5]decane-2,6,8,10-tetraone as a colorless solid. HPLC Ret. time: 2.201 min; MS (APCl, m/z): 436 [M−H]−; 438 [M+H]+.

1. stirringthe mixture was stirred for 5 minutes at 80° C
2. extractionextracted 3× with ethyl acetate
3. dry with materialThe combined organic phases were dried over sodium sulphate
4. filtrationfiltered
5. concentrationconcentrated in vacuo
6. customThe residue was purified by silica gel chromatography (3:1 hexane-ethyl acetate)