Dimethyl Sulfate → (1-Hydroxy-6-methoxy-4-methoxymethyl-1,3-dihydro-benzo[c][1,2]oxaborol-3-yl)-acetic acid ethyl ester

HRID 1798104Notes

Reaction equation

HRID 1798104 reaction equation
[CH2:1]([O:3][C:4](=[O:20])[CH2:5][CH:6]1[O:10][B:9]([OH:11])[C:8]2[CH:12]=[C:13]([OH:19])[CH:14]=[C:15]([CH2:16][O:17][CH3:18])[C:7]1=2)[CH3:2].[C:21]([O-])([O-])=O.[K+].[K+].COS(OC)(=O)=O>CC(C)=O.CCOC(C)=O>[CH2:1]([O:3][C:4](=[O:20])[CH2:5][CH:6]1[O:10][B:9]([OH:11])[C:8]2[CH:12]=[C:13]([O:19][CH3:21])[CH:14]=[C:15]([CH2:16][O:17][CH3:18])[C:7]1=2)[CH3:2]

Participants

6

Reactant 3

HCID 6497Dimethyl SulfateHCID 11430Potassium CarbonateHCID 58292640(1,6-Dihydroxy-4-methoxymethyl-1,3-dihydro-benzo[c][1,2]oxaborol-3-yl)-acetic acid ethyl ester

Product 1

HCID 58292600(1-Hydroxy-6-methoxy-4-methoxymethyl-1,3-dihydro-benzo[c][1,2]oxaborol-3-yl)-acetic acid ethyl esterYield 32%

Reagents, catalysts & solvents 2

HCID 180AcetoneSolventHCID 8857Ethyl AcetateSolvent

Procedure

To a mixture of (1,6-dihydroxy-4-methoxymethyl-1,3-dihydro-benzo[c][1,2]oxaborol-3-yl)-acetic acid ethyl ester (0.18 g, 0.64 mmol) and K2CO3 (0.44 g, 3.2 mmol) in acetone was added Me2SO4 (0.16 g, 1.28 mmol). The mixture was stirred at room temperature for 16 hours then diluted with EtOAc. The organic extracts were washed with HCl (aq), dried and concentrated in vacuo. The residue was purified by silica gel flash column chromatography to give (1-hydroxy-6-methoxy-4-methoxymethyl-1,3-dihydro-benzo[c][1,2]oxaborol-3-yl)-acetic acid ethyl ester (0.060 g, 32%). 1H NMR (400 MHz, MeOD-d4) δ 7.08 (s, 1H), 6.99 (s, 1H), 5.62 (m, 1H), 5.50 (m, 2H), 4.08 (m, 2H), 3.80 (s, 3H), 3.37 (s, 3H), 3.12 (m, 1H), 2.17 (m, 1H), 1.20 (m, 3H).

Workup

  1. washThe organic extracts were washed with HCl (aq)
  2. customdried
  3. concentrationconcentrated in vacuo
  4. customThe residue was purified by silica gel flash column chromatography

Sources & evidence

ORD record
ord-63963e4e8abf4321be4162590248d573
Source dataset
uspto-grants-2013_01
Patent number
US08343944B2

Reaction notes

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