Piperidine, 1-(3-bromopropyl)-, hydrobromide synthesis

Yield:58689-34-2 78%

Reaction Conditions:

with hydrogen bromide in water at 0; for 4.16667 h;Heating / reflux;

Steps:

52.52.1

Step 52.1 : 1-Piperidinepropanol (1.00 ml_, 6.59 mmol) was added to 48% HBr (5 mL) at 0 ⁰C, stood for 10 mins, then heated under a distillation apparatus until ca. 2 mL of water distilled off. The reaction was refluxed for a further 4h, and then the remaining HBr distilled off until the residue started to foam. After cooling to 50 ⁰C, acetone was added. The resulting precipitate was stood at 0 ⁰C for 1h, then filtered off, washed with acetone and dried to leave 1-(3-bromopropyl)piperidine hydrobromide as a white solid (1.47g, 78%). ¹H NMR δ (400 MHz, d₆-DMSO) 9.09 (br s, 1 H), 3.59 (t, J 6.5 Hz, 2H), 3.44 (d, J 12.1 Hz, 2H), 3.13 (m, 2H), 2.89 (m, 2H), 2.23 (m, 2H), 1.81 (m, 2H), 1.75-1.57 (m, 3H), 1.38 ( m, 1H). LCMS (APCI⁺) 206 (MH⁺ with ⁷⁹Br, 100%), 208 (MH⁺ with ⁸¹Br, 90%).

References:

WO2009/8748,2009,A1 Location in patent:Page/Page column 84