반응 #166194

반응 방정식

4-bromomethyl-2,3-difluoro-benzoic acid tert-butyl ester

trimethylamine N-oxide

→

title compound

수율 43.0%

2,3-Difluoro-4-formyl-benzoic acid tert-butyl ester

수율 43.0%

용매

DMSO

DCM

반응 조건

후처리

1. 1
   농축before being concentrated in vacuo
2. 2
   기타The resultant residue was partitioned between iced water and ethyl acetate
3. 3
   기타The organic layer was separated
4. 4
   세척washed with brine twice
5. 5
   건조dried (Na2SO4)
6. 6
   여과filtered
7. 7
   기타evaporated in vacuo

실험 절차

To a solution of 4-bromomethyl-2,3-difluoro-benzoic acid tert-butyl ester (12.9 g, 42.1 mmol) in DMSO (80 mL) and DCM (40 mL) at 0° C. was added trimethylamine N-oxide (3.4 g, 45.3 mmol). The reaction mixture was stirred at room temperature for 18 hours before being concentrated in vacuo. The resultant residue was partitioned between iced water and ethyl acetate. The organic layer was separated and washed with brine twice, dried (Na2SO4), filtered and evaporated in vacuo. The resultant residue which was subjected to flash chromatography (Si—PPC, gradient 0% to 10%, TBME in cyclohexane) to afford the title compound as a white solid (4.34 g, 43%). 1H NMR (CDCl3, 400 MHz) 10.38 (1 H, d, J=0.8 Hz), 7.71 (1 H, dddd, J=7.4, 5.6, 1.7, 0.8 Hz), 7.63 (1 H, ddd, J=7.4, 5.6, 1.5 Hz), 1.61 (9 H, s).

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