Reaktion #1834

Reaktionsgleichung

sodium methoxide

α-bromo-o-tolunitrile

2-hydroxy-5-methylbenzaldehyde

sodium methoxide

ethanol

→

product

Ausbeute 63.3%

2-(2-Cyanophenyl)-5-methylbenzofuran

Ausbeute 63.3%

Lösungsmittel

dimethylformamide

dimethylformamide

dimethylformamide

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeA 500 mL 3-neck round bottom flask equipped with a magnetic stirrer
2. 2
   Temperaturto cool for one hour
3. 3
   workup.ADDITIONwas added
4. 4
   Temperaturthe resulting mixture heated at 90° C. for 1.5 hours
5. 5
   EinengenThe reaction mixture was concentrated under vacuum at 50° C.
6. 6
   Sonstigeto give a brown solid that
7. 7
   Filtrationfiltered
8. 8
   SonstigeThe solids were triturated with 200 mL of methanol
9. 9
   Filtrationfiltered
10. 10
    Waschenwashed with additional methanol
11. 11
    Sonstigeair dried
12. 12
    SonstigeAfter drying in a dessicator under high vacuum

Vorschrift

A 500 mL 3-neck round bottom flask equipped with a magnetic stirrer, dropping funnel, thermometer and nitrogen bubbler was charged with 10.7 g (108 mmol) of sodium methoxide and 75 mL of absolute ethanol. A solution of 24.9 g (183 mmol) of 2-hydroxy-5-methylbenzaldehyde in 75 mL of dry dimethylformamide was added dropwise over 15 minutes. The mixture was stirred for 20 minutes then treated dropwise over 20 minutes with a solution of 34.8 g (177 mmol) of α-bromo-o-tolunitrile in 75 mL of dry dimethylformamide. The mixture was heated at 75° C. for 30 minutes, then allowed to cool for one hour. A suspension of 10.7 g (188 mmol) of sodium methoxide in 20 mL of dry dimethylformamide was added and the resulting mixture heated at 90° C. for 1.5 hours. The reaction mixture was concentrated under vacuum at 50° C. to give a brown solid that was slurried in 100-200 mL of cold water and filtered. The solids were triturated with 200 mL of methanol, filtered, washed with additional methanol, then air dried. After drying in a dessicator under high vacuum, 26.1 g (112 mmol, 63%) of the product was isolated as a beige solid. 1H NMR (200 MHz,CDCl3): 2.45 (s,3H), 7.17 (d,8 Hz,1H), 7.4 (m,3H), 7.6-7.8 (m,3H), 8.10 (d,8 Hz,1H).

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