Hydrochloric Acid → Tamsulosin Hydrochloride

Participants

Reaction Steps

To a solution of tamsulosin 1 (2.011 g, 4.917 mmol) in CH2Cl2 (50 mL) was bubbled with excess dry HCl(g) at 0-5° C. for 1.0 h. The resultant precipitate was filtered and dried under vacuum at room temperature to obtain tamsulosin•HCl (2.091 g, 4.699 mmol) as white solids in 96% yield: mp (recrystallized from 50% MeOH in EtOH) 230-231° C.; specific rotation α D20=−5.3843°; 1H NMR (D2O, 400 MHz) δ 1.14-1.17 (m, 6 H, NCHCH3+OCH2CH3), 2.71-2.76 (m, 1 H, ArCHH), 2.95-3.00 (m, 1 H, ArCHH), 3.36-3.43 (m, 2 H, NCH2), 3.53-3.55 (m, 1 H, NCH), 3.75 (s, 3 H, OCH3), 3.94-3.97 (m, 2 H, MeCH2O), 4.04-4.19 (m, 2 H, OCH2CH2), 6.84-6.96 (m, 5 H, ArH), 7.35 (d, J=8.8 Hz, 1 H, ArH), 7,54 (s, 1 H, ArH); IR (neat) 3304 (m), 3168 (m), 2981 (m), 1610 (m), 1589 (m), 1500 (s), 1458 (m), 1392 (m), 1339 (s), 1251 (s), 1215 (s), 1160 (s), 1128 (s), 1072 (m), 1046 (m), 1018 (m), 820 (m), 749 (s), 718 (m) cm−1.

Provenance & Evidence