Sodium Sulfite → 1-(Benzyloxy)-3-chloropropan-2-one
Reaction equation
[CH2:1]([O:8][CH2:9][CH:10]([OH:13])[CH2:11][Cl:12])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.C([O-])(O)=O.[Na+].[Na+].[Br-].[O-]Cl.[Na+].[O-]S([O-])=O.[Na+].[Na+]>C(OCC)(=O)C.O>[CH2:1]([O:8][CH2:9][C:10](=[O:13])[CH2:11][Cl:12])[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1Participants
Reactant 5
Product 1
Reagents, catalysts & solvents 2
Conditions
- Temperature
- 0 °C
Procedure
To a solution of 1-benzyloxy-3-chloro-propan-2-ol (10.0 g, 50.0 mmol) [prepared according to Journal of Organic Chemistry (1990), 55, 4897] in ethyl acetate (125 mL) was added a solution of NaHCO3 (12.6 g, 150 mmol) and NaBr (5.66 g, 55.0 mmol) in water (75 mL). After cooling of the biphasic mixture to 0° C., 2,2,6,6-Tetramethyl-piperidin-1-yl)oxyl (“TEMPO”) (391 mg, 2.50 mmol) was added in one portion followed by dropwise addition of NaOCl (6 wt % in water, 85.4 mL, 75.0 mmol) to the vigorously stirred solution. After completion of the addition, stirring at 0° C. was continued for 30 min. Subsequently, a solution of aqueous Na2SO3 was added until the reaction mixture had completely discolored. Additional solid Na2SO3 was added to saturate the aqueous phase. The mixture was transferred to a separation funnel and the layers were separated. The organic layer was washed with brine (100 mL), dried (Na2SO4), filtered and concentrated under reduced pressure (at 20° C.). The remaining oil was used without further purification. 1H NMR (400 MHz, CDCl3) 4.26 (s, 2H), 4.33 (s, 2H), 4.62 (s, 2H), 7.31-7.45 (m, 5H).
Workup
- addition2,2,6,6-Tetramethyl-piperidin-1-yl)oxyl (“TEMPO”) (391 mg, 2.50 mmol) was added in one portion
- additionAfter completion of the addition
- concentrationto saturate the aqueous phase
- customThe mixture was transferred to a separation funnel
- customthe layers were separated
- washThe organic layer was washed with brine (100 mL)
- dry with materialdried (Na2SO4)
- filtrationfiltered
- concentrationconcentrated under reduced pressure (at 20° C.)
- customThe remaining oil was used without further purification
Sources & evidence
- ORD record
- ord-fe0fe9f00f5e4c10817d47cf25ef3841
- Source dataset
- uspto-grants-2015_05
- Patent number
- US09024019B2
Reaction notes
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