Potassium Carbonate → (4R,5R)-2,2-dimethyl-4-hydroxymethyl-5-[4-(methylsulfonyl)phenyl]-1,3-oxazolidine
Reaction equation
C(O[C:4](=[O:19])[C@@H:5]([NH2:18])[C@@H:6]([C:8]1[CH:13]=[CH:12][C:11]([S:14]([CH3:17])(=[O:16])=[O:15])=[CH:10][CH:9]=1)[OH:7])C.[BH4-].[K+].N[C@H:23]([CH2:36]O)[C@@H:24](C1C=CC(S(C)(=O)=O)=CC=1)O.C(=O)([O-])[O-].[K+].[K+]>CO.CC(C)=O.C1(C)C=CC=CC=1>[CH3:24][C:23]1([CH3:36])[NH:18][C@H:5]([CH2:4][OH:19])[C@@H:6]([C:8]2[CH:9]=[CH:10][C:11]([S:14]([CH3:17])(=[O:15])=[O:16])=[CH:12][CH:13]=2)[O:7]1Participants
Reactant 4
Product 1
Reagents, catalysts & solvents 3
Conditions
- Temperature
- 80 °C
Procedure
(2S,3R)-Ethyl-2-amino-3-[4-(methylsulfonyl)phenyl]-3-hydroxy-propanoate (Compound IV) (100 g, 0.3480 moles) in 500 mL of methanol reacts with potassium borohydride (28.2 g, 0.5220 moles) over 4-8 hours at 50-60° C. to quantitatively yield (1R,2R)-2-amino-1-[4-(methylsulfonyl)phenyl]-1,3-propandiol (Compound VII: R1 is methylsulfonyl) (85.36 g, 0.3480 moles) in solution. Toluene (500 mL) and acetone (500 mL) replace methanol which distills off. Addition of potassium carbonate (6.9 g, 0.0696 moles) with heating at 75-85° C. for 12-18 hours yields (4R,5R)-2,2-dimethyl-4-hydroxymethyl-5-[4-(methylsulfonyl)phenyl]-1,3-oxazolidine (Compound VIII: R1 is methylsulfonyl and R2 and R3 are methyl). Addition of potassium carbonate (19.0 g, 0.1914 moles) and acetyl chloride (30.0 g, 0.3828 moles) at 20-25° C. for 2-4 hours then addition of water (500 mL) precipitates the crude product. Filtration, washing with water (250 mL) then drying yields (4R,5R)-3-acetyl-2,2-dimethyl-4-hydroxymethyl-5-[4-(methylsulfonyl)phenyl]-1,3-oxazolidine (Compound II).
Workup
- distillationdistills off
Sources & evidence
- ORD record
- ord-80bc1020e6714f7f8e7362c429caf799
- Source dataset
- uspto-grants-2010_08
- Patent number
- US07786329B2
Reaction notes
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