Hydrochloric Acid → 220475-76-3
Reaction equation
[Cl:1][C:2]1[CH:3]=[C:4]([C@@H:8]([OH:29])[CH2:9][NH:10][C@H:11]([CH3:28])[CH2:12][C:13]2[CH:27]=[CH:26][C:16]3[O:17][C@@H:18]([C:21]([O:23]CC)=[O:22])[CH2:19][O:20][C:15]=3[CH:14]=2)[CH:5]=[CH:6][CH:7]=1.O.Cl>C(O)C>[Cl:1][C:2]1[CH:3]=[C:4]([C@@H:8]([OH:29])[CH2:9][NH:10][C@H:11]([CH3:28])[CH2:12][C:13]2[CH:27]=[CH:26][C:16]3[O:17][C@@H:18]([C:21]([OH:23])=[O:22])[CH2:19][O:20][C:15]=3[CH:14]=2)[CH:5]=[CH:6][CH:7]=1Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Procedure
To a solution of ethyl 6-(2-(R)-((2-(R)-(3-chlorophenyl)-2-hydroxyethyl)amino)propyl)-2,3-dihydro-1,4-benzodioxin-2-(R)-carboxylate (650 mg) in ethanol (2 ml) were added water (20 ml) and concentrated hydrochloric acid (0.32 ml). This solution was stirred under reflux-heating for 5 hours while removing ethanol with Dean-Stark apparatus. After the solution was concentrated under reduced pressure, acetonitrile/water (1/1) (11 ml) was added to the residue, which was then dissolved under heating. The solution was neutralized with a 5% aqueous solution of sodium hydrogencarbonate. Acetonitrile (20 ml) was added, and the crystals precipitated were dissolved under heating. The resulting solution was filtered under heating and then cooled, and the resulting crystals were filtered to give 6-(2-(R)-((2-(R)-(3-chlorophenyl)-2-hydroxyethyl)amino)-propyl)-2,3-dihydro-1,4-benzodioxin-2-(R)-carboxylic acid (412 mg). The HPLC-2 analysis of the optical isomer showed 96.5% purity (R/S=96.5/3.5, the purity of the material optical isomer used=90.5%).
Workup
- temperatureunder reflux-heating for 5 hours
- customwhile removing ethanol with Dean-Stark apparatus
- concentrationAfter the solution was concentrated under reduced pressure, acetonitrile/water (1/1) (11 ml)
- additionwas added to the residue, which
- dissolutionwas then dissolved
- temperatureunder heating
- additionAcetonitrile (20 ml) was added
- customthe crystals precipitated
- dissolutionwere dissolved
- temperatureunder heating
- filtrationThe resulting solution was filtered
- temperatureunder heating
- temperaturecooled
- filtrationthe resulting crystals were filtered
Sources & evidence
- ORD record
- ord-f94f4aeab23745dc852a5f53ca4c4428
- Source dataset
- uspto-grants-2001_12
- Patent number
- US06329533B2
Reaction notes
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