Hydrogen Peroxide → 4-Methoxybenzyl 5-hydroxy-2,2-dimethylvalerate
Reaction equation
[CH3:1][C:2]([CH3:18])([CH2:15][CH:16]=[CH2:17])[C:3]([O:5][CH2:6][C:7]1[CH:12]=[CH:11][C:10]([O:13][CH3:14])=[CH:9][CH:8]=1)=[O:4].B1C2CCCC1CCC2.[OH-:28].[Na+].OO>O>[OH:28][CH2:17][CH2:16][CH2:15][C:2]([CH3:18])([CH3:1])[C:3]([O:5][CH2:6][C:7]1[CH:8]=[CH:9][C:10]([O:13][CH3:14])=[CH:11][CH:12]=1)=[O:4]Participants
Conditions
- Temperature
- 60 °C
Procedure
A mixture of 4-methoxybenzyl 2,2-dimethyl-4-pentenoate (9.50 g, 38 mmol) and 9-BBN (115 mL, 57 mmol, 0.5 M in THF) was stirred at 60° C. for 60 min, whereupon the reaction mixture was cooled to −5° C. H2O (35 mL) was added, the reaction mixture was stirred for 5 min at −5° C., an aqueous solution of NaOH (35 mL, 3M) was added and the reaction mixture was stirred for a further 10 min at −5° C. An aqueous solution of H2O2 (35 mL, 30%) was added dropwise and the temperature of the reaction mixture was allowed to assume room temperature, whereupon the reaction mixture was stirred for 30 min at room temperature. After evaporation, water (200 mL) was added and the resulting mixture was extracted with CH2Cl2 (5×200 mL). The combined organic layers were dried (Na2SO2) and concentrated under reduced pressure. The crude product was column chromatographed (silica gel, 1→8% MeOH in CH2Cl2), to give 6.32 g of 4-methoxybenzyl 5-hydroxy-2,2-dimethylvalerate.
Workup
- temperaturewas cooled to −5° C
- stirringthe reaction mixture was stirred for 5 min at −5° C.
- stirringthe reaction mixture was stirred for a further 10 min at −5° C
- customto assume room temperature, whereupon the reaction mixture
- stirringwas stirred for 30 min at room temperature
- customAfter evaporation, water (200 mL)
- additionwas added
- extractionthe resulting mixture was extracted with CH2Cl2 (5×200 mL)
- dry with materialThe combined organic layers were dried (Na2SO2)
- concentrationconcentrated under reduced pressure
- customchromatographed (silica gel, 1→8% MeOH in CH2Cl2)
Sources & evidence
- ORD record
- ord-f945b8ee89544317877d45e1a73d70d5
- Source dataset
- uspto-grants-2002_10
- Patent number
- US06458772B1
Reaction notes
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