反应详情

146 g (0.8 mol) of 2-bromobenzaldehyde, 85.6 g (0.8 mol) of 3-pyridinealdehyde, 20 g (0.08 mol) of 3-ethyl-5-(2-hydroxyethyl)-4-methylthiazoliumbromide and 40.4 g (0.4 mol) of triethylamine in 500 ml of ethanol were heated at 75° C. for 16 hours. Thereafter, the ethanol was distilled off and the residue was taken up in methylene chloride. The solution was washed twice with water and then extracted twice with 300 ml of 4N hydrochloric acid. The acidic aqueous phase was then rendered slightly alkaline with 4N sodium hydroxide solution and extracted three times with methylene chloride. After the solvent had been distilled off, the crude product was stirred with isopropanol, filtered off under suction and dried to give a product of melting point 105°-108° C.

1. distillationThereafter, the ethanol was distilled off
2. washThe solution was washed twice with water
3. extractionextracted twice with 300 ml of 4N hydrochloric acid
4. extractionextracted three times with methylene chloride
5. distillationAfter the solvent had been distilled off
6. filtrationfiltered off under suction
7. customdried
8. customto give a product of melting point 105°-108° C.