HCID 2763349, compound → HCID 18626916, compound

Participants

Reaction Steps

Method A. A solution of 10 (0.25 g, 0.77 mmol) in 2 mL of methanesulfonic acid was heated at 60° C. for 3 d. The reaction mixture was diluted with ether (100 mL) and washed with sat. NaHCO3 (20 mL×3) and sat. NaCl (20 mL). The organic layer was dried (MgSO4) and evaporated under reduced pressure. The resulting residue was purified by flash chromatography (EtOAc/hexanes 1:1) to give 14 (0.14 g, 59%) as a colorless solid: 1H NMR (CDCl3) d 2.00 (p, 2H, J=5.7), 3.52 (t, 2H, J=5.7), 4.32 (t, 2H, J=5.7), 6.58 (s, 1H), 10.10 (br, 1H); 13C NMR (CD3COCD3) d 22.2 (e), 41.3 (e), 66.6 (e), 99.1 (e), 109.4 (e), 115.0 (o), 127.7 (e), 153.8 (e); UV (CH3OH) 1max 329, 275 nm; MS m/z (relative intensity) 311 (M++5, 50), 309 (M++3, 100), 307 (M++1, 50); Anal. Calcd for C8H8N2OBr2: C, 31.20; H, 2.62; N, 9.10; Found: C, 31.17; H, 2.51; N, 9.29. Method B. To a stirred mixture of 10 (0.25 g, 0.77 mmol) and p-toluenesulfonyl chloride (0.16 g, 0.77 mmol) in 10 mL of THF was added triethylamine (0.6 mL, 4.27 mmol) at room temperature. The mixture was heated at 80° C. overnight. The solvent was evaporated under reduced pressure and the resulting residue was purified by flash chromatography (CH2Cl2/MeOH 19:1) to give 14 (0.15 g, 63%) as a colorless solid.

Provenance & Evidence