[C:1]([C:4]1[CH:13]=[C:12]2[C:7]([CH:8]=[CH:9][C:10]([NH:14][C:15](=[O:21])[O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[CH:11]2)=[CH:6][CH:5]=1)(=[O:3])[CH3:2].C1C(=O)N([Br:29])C(=O)C1.C([O-])([O-])=O.[K+].[K+]>CC#N>[C:1]([C:4]1[CH:13]=[C:12]2[C:7]([CH:8]=[CH:9][C:10]([NH:14][C:15](=[O:21])[O:16][C:17]([CH3:20])([CH3:19])[CH3:18])=[C:11]2[Br:29])=[CH:6][CH:5]=1)(=[O:3])[CH3:2]A mixture of carbamate 170 (420 mg, 1.47 mmol), NBS (292 mg, 1.62 mmol) and K2CO3 (244 mg, 1.77 mmol) in MeCN (10 mL) was heated at 40° C. under N2 for 30 min then concentrated under reduced pressure. EtOAc and water were added to the residue, and the EtOAc portion was washed with water, brine and dried to give tert-butyl 7-acetyl-1-bromo-2-naphthylcarbamate (171) (530 mg, 99%) as a colorless solid: mp (petroleum ether/EtOAc) 114-117° C.; 1H NMR (CDCl3) δ 8.70 (s, 1H), 8.50 (d, J=9.0 Hz, 1H), 7.97 (dd, J=3.5, 1.6 Hz, 1H), 7.84 (d, J=8.8 Hz, 1H), 7.81 (d, J=9.6 Hz, 1H), 7.34 (br s, 1H), 2.76 (s, 3H), 1.58 (s, 9H); 13C NMR δ 197.9, 152.4, 136.0, 135.8, 133.0, 131.5, 128.7, 128.5, 128.0, 123.1, 122.0, 111.0, 81.6, 28.3, 26.7. Anal. (C17H18BrNO3) C, H, N.
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