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

Participants

Reaction Steps

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).

Provenance & Evidence