Propylamine → HCID 4716567, compound

To 4-bromobenzaldehyde (100 g, 0.54 mol) and n-propylamine (36.3 g, 0.60 mol) in methanol (100 mL) was added 5% platinum on carbon (1.00 g). This mixture was shaken in a Parr hydrogenation reactor overnight to complete formation of the Schiff base. The reaction was then hydrogenated under 4 atmospheres of hydrogen until the theoretical uptake of hydrogen had been consumed. The catalyst was removed by filtration through a 0.45 m nylon frit and washed with methanol. The filtrate was concentrated under reduced pressure and the residue obtained dissolved in ether (500 mL). The ether solution was washed with water (2×100 mL), 10% sodium bicarbonate solution (2×100 mL), and water (2×100 mL), dried over magnesium sulfate, filtered, and concentrated under reduced pressure to afford the crude title compound (121.34 g). GC-MS showed this material to be 98.5% pure product containing 1.5% of the desbromo compound; the yield is 96.93% based on the GC purity of the product obtained. A sample of this material was purified by bulb-to-bulb distillation (bath temperature 130°-150° C., 0.18 torr). 1H NMR (CDCl3, 300 MHz) d 0.92 (t, J=7.4 Hz, 3H), 1.36 (bs, 1H) 1.53 (tq, J1 =J2 =7.4 Hz, 2H) 2.57 (t, J=7.4 Hz, 2H),3.74 (s, 2H), 7.20 (d, J=9 Hz, 2H), 7.44 (d, J=9 Hz, 2H). IR (film) 1430, 1060 cm-1. MS (DCl/NH3) m/e 228, 230 (M+H)+.

1. customhad been consumed
2. customThe catalyst was removed by filtration through a 0.45 m nylon frit
3. washwashed with methanol
4. concentrationThe filtrate was concentrated under reduced pressure
5. customthe residue obtained
6. washThe ether solution was washed with water (2×100 mL), 10% sodium bicarbonate solution (2×100 mL), and water (2×100 mL)
7. dry with materialdried over magnesium sulfate
8. filtrationfiltered
9. concentrationconcentrated under reduced pressure

ORD record

ord-5c4b3e5dabf346cd8db450a38994b249

Source dataset

uspto-grants-1993_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05250548