Imidazole → 5-{[tert-butyl(dimethyl)silyl]oxy}-1,3-benzoxazol-2(3H)-one

HRID 1407405Notes

Reaction equation

HRID 1407405 reaction equation
[OH:1][C:2]1[CH:3]=[CH:4][C:5]2[O:9][C:8](=[O:10])[NH:7][C:6]=2[CH:11]=1.N1C=CN=C1.Cl[Si:18]([C:21]([CH3:24])([CH3:23])[CH3:22])([CH3:20])[CH3:19]>CN(C)C=O>[Si:18]([O:1][C:2]1[CH:3]=[CH:4][C:5]2[O:9][C:8](=[O:10])[NH:7][C:6]=2[CH:11]=1)([C:21]([CH3:24])([CH3:23])[CH3:22])([CH3:20])[CH3:19]

Participants

5

Reactant 3

HCID 795ImidazoleHCID 28928tert-Butyldimethylsilyl chlorideHCID 160466715-Hydroxy-1,3-benzoxazol-2(3H)-one

Product 1

HCID 666312795-{[tert-butyl(dimethyl)silyl]oxy}-1,3-benzoxazol-2(3H)-oneYield 87.4%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a solution of 5-hydroxy-1,3-benzoxazol-2(3H)-one (Itoh, et al., J. Org. Chem. 2002 (67):7424-7428) (1.00 g, 6.6 mmol) in anhydrous N,N-dimethylformamide (10 mL) was added imidazole (0.54 g, 7.9 mmol), followed by chloro-tert-butyldimethylsilane (1.10 g, 7.3 mmol). The reaction mixture was stirred at ambient temperature for 16 h and concentrated in vacuo. The crude product was purified by column chromatography with ethyl acetate in hexanes (0 to 50% gradient) to afford 5-{[tert-butyl(dimethyl)silyl]oxy}-1,3-benzoxazol-2(3H)-one (1.53 g, 87%) as a colorless solid: 1H NMR (300 MHz, CDCl3) δ9.04 (br s, 1H), 7.04 (d, J=8.3 Hz, 1H), 6.60-6.53 (m, 2H), 0.98 (s, 9H), 0.19 (s, 6H).

Workup

  1. concentrationconcentrated in vacuo
  2. customThe crude product was purified by column chromatography with ethyl acetate in hexanes (0 to 50% gradient)

Sources & evidence

ORD record
ord-4bf495d9455947b08126a280f5d0a356
Source dataset
uspto-grants-2014_12
Patent number
US08916580B2

Reaction notes

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