Tetrahydrofuran → Aleglitazar
Reaction equation
C([C@H]1COC(=O)N1C(=O)[C@@H:15]([O:41][CH3:42])[CH2:16][C:17]1[C:22]2[S:23][CH:24]=[CH:25][C:21]=2[C:20]([O:26][CH2:27][CH2:28][C:29]2[N:30]=[C:31]([C:35]3[CH:40]=[CH:39][CH:38]=[CH:37][CH:36]=3)[O:32][C:33]=2[CH3:34])=[CH:19][CH:18]=1)C1C=CC=CC=1.[OH-:44].[Na+].C1[CH2:50][O:49]CC1>>[CH3:42][O:41][C@@H:15]([CH2:16][C:17]1[C:22]2[S:23][CH:24]=[CH:25][C:21]=2[C:20]([O:26][CH2:27][CH2:28][C:29]2[N:30]=[C:31]([C:35]3[CH:40]=[CH:39][CH:38]=[CH:37][CH:36]=3)[O:32][C:33]=2[CH3:34])=[CH:19][CH:18]=1)[C:50]([OH:49])=[O:44]Participants
Procedure
0.195 g of the above prepared (S)-4-benzyl-3-((2S)-2-methoxy-3-{4-[2-(5-methyl-2-phenyl-oxazol-4-yl)-ethoxy]-benzo[b]thiophen-7-yl}-propionyl)-oxazolidin-2-one (0.32 mmol) was dissolved in 2.25 ml of THF and treated with 0.81 ml of 1N NaOH (2.5 eq.). The reaction mixture was kept at 0° and progress of the hydrolysis followed by TLC. After 1 h the reaction mixture was quenched by pouring onto crashed ice/HCl. Twofold extraction with AcOEt, washing with water and brine, drying over magnesium sulfate, and evaporation of the solvents left a crude product, which was purified by twofold crystallisation from AcOEt/hexane to remove the chiral auxiliary. Thereby, 0.102 g of the title compound was obtained as white solid, mp.118-120°. The enantiomeric excess was judged according to 1H-NMR in the presence of a large excess of optically pure trifluoromethyl-anthryl-ethanol to be >95%. According to chiral HPLC (Chiralpak-AD) it amounts to 99.3%.
Workup
- customwas kept at 0°
- customAfter 1 h the reaction mixture was quenched
- additionby pouring
- extractionTwofold extraction with AcOEt
- washwashing with water and brine
- dry with materialdrying over magnesium sulfate, and evaporation of the solvents
- waitleft a crude product, which
- customwas purified by twofold crystallisation from AcOEt/hexane
- customto remove the chiral auxiliary
Sources & evidence
- ORD record
- ord-2ed97b20915840d9acde9731811a5f31
- Source dataset
- uspto-grants-2003_11
- Patent number
- US06642389B2
Reaction notes
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