Sodium hydride → 4-{2-Cyano-2-[(diphenylmethylene)amino]ethyl}-3-fluorobenzonitrile

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

To a suspension of sodium hydride (2.62 g) in dimethylformamide (100 ml) at 0° C. was slowly added a solution of [(diphenylmethylidene)amino]acetonitrile (13.20 g) in 40 ml of dimethylformamide. The reaction temperature varied between 2 and 8° C. during the addition. The color went from yellow to brown with gas evolution. The reaction mixture was stirred at 0° C. for 10 more minutes then 4-(bromomethyl)-3-fluorobenzonitrile from step 1 (12.72 g) was added very quickly in 60 ml of dimethylformamide. The temperature rose to 27° C. and the cold bath was removed. The reaction was stirred for 4 h. The flask content was poured into sodium dihydrogen phosphate solution (300 ml) and icy water (1.4 L). The mixture turned yellow and a big lump formed along with very small amounts of fine powder. The fine solid was filtered and the lump kept in the Erlenmeyer. The lump was dissolved in ether (500 ml) and put in a separating funnel along with water (200 ml). The phases were separated and the organic layer was washed with brine (100 ml) and dried over magnesium sulfate. The organic phase is concentrated under reduced pressure to give 4-{2-cyano-2-[(diphenylmethylene)amino]ethyl}-3-fluorobenzonitrile an orange solid that was used as such in the next step.

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