反应详情

The procedure used in Example 68 is followed. In a 250 ml round-bottomed flask under an argon atmosphere, reflux, for 6 hours, a suspension of 5 g of (2-amino-6-methylphenyl)amide of 9-oxo-9H-fluorene-4-carboxylic acid, obtained in the previous stage, in 100 ml of acetic acid. After cooling, bring to dryness under reduced pressure. Take the residue up in 25 ml of water then bring to pH=8 by addition of a saturated aqueous solution of sodium hydrogen carbonate. The precipitate that formed is filtered off, washed with water, and made into a paste with diisopropyl ether, and in this way, we obtain 4.7 g of 4-(4-methyl-1H-benzimidazol-2-yl)-9H-fluoren-9-one, in the form of an orange powder, which is used as it is in the following stage, with the following characteristics:

1. temperatureIn a 250 ml round-bottomed flask under an argon atmosphere, reflux, for 6 hours
2. temperatureAfter cooling
3. customThe precipitate that formed
4. filtrationis filtered off
5. washwashed with water