Lansoprazole → Dexlansoprazole

HRID 432788Notes

Reaction equation

HRID 432788 reaction equation
[CH3:1][C:2]1[C:3]([O:20][CH2:21][C:22]([F:25])([F:24])[F:23])=[CH:4][CH:5]=[N:6][C:7]=1[CH2:8][S+:9]([O-:19])[C:10]1[NH:11][C:12]2[CH:13]=[CH:14][CH:15]=[CH:16][C:17]=2[N:18]=1.CCCCCC.C(N(CC)CC)C.CCCCCC.CC(O)C>CC(O)C>[CH3:1][C:2]1[C:7]([CH2:8][S@:9]([C:10]2[NH:11][C:12]3[CH:13]=[CH:14][CH:15]=[CH:16][C:17]=3[N:18]=2)=[O:19])=[N:6][CH:5]=[CH:4][C:3]=1[O:20][CH2:21][C:22]([F:25])([F:23])[F:24]

Participants

6

Procedure

Lansoprazole (racemate) (34.2 g) was dissolved in 2-propanol (1,710 ml) and hexane (1,140 ml) containing triethylamine (0.2%) and fractionated by HPLC (column: CHIRALCEL OD 50 mm dia.×500 mm, temperature: room temperature, mobile phase: hexane/2-propanol=85/15, flow rate: 60 ml/min, detection wavelength: 285 nm, single injection: about 300 mg) to isolate the individual optical isomers. Fractions of an optical isomer of shorter retention time were combined and concentrated; the individual lots were combined and dissolved in ethanol (250 ml); after triethylamine (3 ml) was added, the solution was filtered through a 0.45 μm filter. After the filtrate was concentrated, hexane was added, and the filtrate was again evaporated to dryness to yield R(+)-lansoprazole (9.31 g, optical purity 98.3% ee) as an amorphous substance.

Workup

  1. customto isolate the individual optical isomers
  2. concentrationconcentrated
  3. dissolutiondissolved in ethanol (250 ml)
  4. additionafter triethylamine (3 ml) was added
  5. filtrationthe solution was filtered through a 0.45 μm
  6. filtrationfilter
  7. concentrationAfter the filtrate was concentrated
  8. additionhexane was added
  9. customthe filtrate was again evaporated to dryness

Sources & evidence

ORD record
ord-4846020fce5a49f0af80e4ff8bd29c40
Source dataset
uspto-grants-2003_12
Patent number
US06664276B2

Reaction notes

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