Реакция #710555

Уравнение реакции

lithium bromide

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

triethylamine

methanesulfonyl chloride

→

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

Выход 96.3%

Растворители

acetone

Условия реакции

Обработка

1. 1
   ФильтрацияThe reaction mixture was filtered
2. 2
   Другоеto remove the precipitated salts
3. 3
   Промывкаthe 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
   ДругоеThe reaction mixture was partitioned between water (25 mL) and ethyl acetate (25 mL)
6. 6
   Экстракцияthe aqueous layer was extracted with further ethyl acetate (25 mL)
7. 7
   ПромывкаThe combined organics were washed with brine (25 mL)
8. 8
   Сушкаdried over Na2SO4
9. 9
   Концентрированиеconcentrated in vacuo

Методика

To a stirring solution of (Z)-tert-butyl 3-fluoro-2-(hydroxymethyl)-allylcarbamate (0.50 g, 2.44 mmol) in acetone (15 mL) at 0° C. under N2 was added sequentially triethylamine (0.51 mL, 3.65 mmol) and methanesulfonyl chloride (0.23 mL, 2.92 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 (1.06 g, 12.18 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 (Z)-tert-butyl 2-(bromomethyl)-3-fluoroallylcarbamate as a pale yellow oil (0.63 g, 96%). 1H-NMR (300 MHz; CDCl3) δ ppm: 1.47 (9H, s), 3.80 (2H, br s), 4.09 (2H, d, J 2.6 Hz), 4.75 (1H, br s), 6.65 (1H, d, J 81.9 Hz).

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