반응 #710556

반응 방정식

lithium bromide

(E)-tert-butyl 3-fluoro-2-(hydroxymethyl)-allylcarbamate

triethylamine

methanesulfonyl chloride

→

(E)-tert-butyl 2-(bromomethyl)-3-fluoroallylcarbamate

수율 93.1%

용매

acetone

반응 조건

후처리

1. 1
   여과The reaction mixture was filtered
2. 2
   기타to remove the precipitated salts
3. 3
   세척the filter cake was washed with further acetone (10 mL)
4. 4
   workup.STIRRINGthe resulting suspension was stirred at room temperature for 1 h
5. 5
   기타The reaction mixture was partitioned between water (25 mL) and ethyl acetate (25 mL)
6. 6
   추출the aqueous layer was extracted with further ethyl acetate (25 mL)
7. 7
   세척The combined organics were washed with brine (25 mL)
8. 8
   건조dried over Na2SO4
9. 9
   농축concentrated in vacuo

실험 절차

To a stirring solution of (E)-tert-butyl 3-fluoro-2-(hydroxymethyl)-allylcarbamate (1.20 g, 5.85 mmol) in acetone (20 mL) at 0° C. under N2 was added sequentially triethylamine (1.22 mL, 8.77 mmol) and methanesulfonyl chloride (0.54 mL, 7.02 mmol). The resulting mixture was stirred at this temperature for 30 min. The reaction mixture was filtered to remove the precipitated salts and the filter cake was washed with further acetone (10 mL). The filtrate was charged with lithium bromide (2.54 g, 29.24 mmol) and the resulting suspension was stirred at room temperature for 1 h. The reaction mixture was partitioned between water (25 mL) and ethyl acetate (25 mL) and the aqueous layer was extracted with further ethyl acetate (25 mL). The combined organics were washed with brine (25 mL), dried over Na2SO4 and concentrated in vacuo to give (E)-tert-butyl 2-(bromomethyl)-3-fluoroallylcarbamate as a pale yellow oil (1.46 g, 93%). 1H-NMR (300 MHz; CDCl3) δ ppm: 1.47 (9H, s), 3.97 (2H, dd, J 3.5, 0.7 Hz), 4.02 (2H, br d, J 6.1 Hz), 4.78 (1H, br s), 6.79 (1H, d, J 81.1 Hz).

출처