反応 #1300

反応方程式

benzyl alcohol

KOCN

4-bromo-2-fluorobenzyl bromide

→

O-benzyl N-(4-bromo-2-fluorobenzyl)carbamate

溶媒

DMF

反応条件

後処理

1. 1
   その他drying tube
2. 2
   その他to the stirred reaction mixture by means of a dropping funnel
3. 3
   温度The resulting suspension is subsequently heated
4. 4
   workup.STIRRINGfurther stirred at this temperature for approximately 1.5 h
5. 5
   温度The mixture is then cooled to room temperature
6. 6
   ろ過The salt present in the reaction mixture is filtered off by suction via a frit
7. 7
   その他The solvent and excess benzyl alcohol are removed from the filtrate in vacuo
8. 8
   温度The light yellow oily residue is cooled with ice for crystallization
9. 9
   その他The bright crystalline mass produced
10. 10
    洗浄is washed with water
11. 11
    ろ過filtered
12. 12
    その他dried

実験手順

Anhydrous and amine-free DMF (180 ml) and benzyl alcohol (28 ml) and KOCN (0.247 mol, 20 g) are charged into a 500 ml 2-neck round bottom flask having a reflux condenser and drying tube. A solution of 4-bromo-2-fluorobenzyl bromide (0.075 mol, 20 g) in DMF (20 ml) is added rapidly (in the course of 1 min) at room temperature to the stirred reaction mixture by means of a dropping funnel. The resulting suspension is subsequently heated with stirring to approximately 110° C. and further stirred at this temperature for approximately 1.5 h. The mixture is then cooled to room temperature. The salt present in the reaction mixture is filtered off by suction via a frit. The solvent and excess benzyl alcohol are removed from the filtrate in vacuo. The light yellow oily residue is cooled with ice for crystallization. The bright crystalline mass produced is washed with water, filtered and dried. Yield: 23.2 g (:91.5% of theory) M.p.: 82°-84° C. GC/MS: M+ =337, IR in KBr [cm-1 ]: 3342 (m) N--H, 1689 (s) C=O, 1535 (m) NH--C, 1276 (m) C--O--C

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