Methanol → 4-[3-(4-Butyl-piperidin-1-yl)propyl]-4H-benzo[1,4]thiazin-3-one

Participants

Reaction Steps

NAI (1.24 g, 8.27 mmol), K2CO3 (1.14 g, 8.27 mmol), and 4-butylpiperidine (0.62 g, 4.34 mmol) in acetonitrile (10 mL) were stirred at rt. 4-(3-chloropropyl)-4H-benzo[1,4]thiazin-3-one (1.0 g, 4.14 mmol) in acetonitrile (15 mL) was added via a syringe. The reaction was stirred at 60 C. for 13 hours and then 80 C. for another 25 hours under nitrogen atmosphere and concentrated in vacuo. Water (150 mL) was added and the reaction mixture was extracted with ethyl acetate (3×150 mL). The combined organic phases were dried (Na2SO4) and concentrated in vacuo to give 1.63 g of crude. The crude product was subjected to CC[eluent:EtOAC:MeOH(100:1-5%)] to give the pure title compound. Yield 1.06 g 74.2% HPLC-MS [M+H]+347 (UV/MS(%)=100/99. 1H NMR (CDCl3): δ 0.88 (t, 3H), 1.23 (m, 9H), 1.64 (d, 2H), 1.85 (m, 4H), 2.34 (t, 2H), 2.83 (d, 2H), 3.36 (s, 1H), 4.03 (t, 2H), 6.99 (m, 1H), 7.22 (d, 2H), 7.34 (d, 1H), 13C NMR (CDCl3): δ 14.21, 23.03, 25.23, 29.15, 31.80, 32.63, 35.90, 36.44, 43.28, 54.26, 55.91, 118.18, 123.45, 124.17, 127.27, 128.56, 139.63, 165.19.

Provenance & Evidence