Hydrochloric Acid → Palonosetron hydrochloride

HRID 419299Notes

Reaction equation

HRID 419299 reaction equation
[CH:1]1[CH:6]=[C:5]2[C:7]([N:9]([C@H:15]3[CH:20]4[CH2:21][CH2:22][N:17]([CH2:18][CH2:19]4)[CH2:16]3)[CH2:10][C@H:11]3[CH2:12][CH2:13][CH2:14][C:3](=[C:4]23)[CH:2]=1)=[O:8].[ClH:23].BrN1C(=O)CCC1=O>CO.C(O)C>[CH:1]1[CH:6]=[C:5]2[C:7]([N:9]([C@H:15]3[CH:20]4[CH2:21][CH2:22][N:17]([CH2:18][CH2:19]4)[CH2:16]3)[CH2:10][C@H:11]3[CH2:12][CH2:13][CH2:14][C:3](=[C:4]23)[CH:2]=1)=[O:8].[ClH:23]

Participants

6

Conditions

Temperature
72.5 °C

Procedure

The diastereomeric palonosetron (VIII) (10.0 g) as obtained above was dissolved in 42.0 ml of 5% methanol in ethanol (4.2 volumes). To it hydrochloric acid in ethanol was added and was heated to 70-75° C. Then N-bromosuccinimide (200 mg) was added at reflux. The solution was then cooled to 0 to 5° C. and 5.5 g of the precipitated crude palonosetron hydrochloride (I) was isolated by filtration. This obtained crude palonosetron hydrochloride (I) showing 94.65% of the desired (3aS, S) isomer, 4.14% of the undesired (3aR, S) isomer (Ia) and 0.30% of unreacted compound (VI), when crystallized twice from ethanol-methanol mixture containing 20 mg of N-bromosuccinimide yielded 2.0 g of the title product (I) which was found to contain 99.60% of the titled compound (I), 0.40% (3aR, S) isomer (Ia) and intermediate (IIa) below detection limit by HPLC analysis.

Workup

  1. temperatureat reflux
  2. temperatureThe solution was then cooled to 0 to 5° C.
  3. custom5.5 g of the precipitated crude palonosetron hydrochloride (I)
  4. customwas isolated by filtration
  5. customThis obtained crude palonosetron hydrochloride (I)
  6. customcrystallized twice from ethanol-methanol mixture
  7. additioncontaining 20 mg of N-bromosuccinimide

Sources & evidence

ORD record
ord-ea156cb9a8084aa6b11e6758fdf450e6
Source dataset
uspto-grants-2012_01
Patent number
US08093391B2

Reaction notes

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