Ethanolamine → 1-(2,6-difluorobenzyl)-6-(4-aminophenyl)-5-((benzyl(methyl)amino)methyl)-3-phenylthieno[2,3-d]pyrimidine-2,4(1H,3H)-dione

Participants

Reaction Steps

5-(N-benzyl-N-methylaminomethyl)-1-(2,6-difluorobenzyl)-5-methyl-6-(4-nitrophenyl)-3-phenylthieno[2,3-d]pyrimidine-2,4(1H, 3H)-dione (3.00 g, 4.80 mmol) was dissolved in acetic acid (6.00 ml). A 20% titanium (III) chloride solution (22.22 g, 28.82 mmol) was added thereto, and the mixture was stirred at room temperature for 1 hour (slight exothermic). Citric acid monohydrate (7.07 g) was added to the reaction solution to dissolve it, and water (30 ml) and 2-butanone (50 ml) were added thereto. 2-aminoethanol (15 ml) was added thereto while the temperature of the solution was maintained below 40° C., and the mixture was stirred at room temperature for 20 minutes. The organic layer was separated, and the aqueous layer was reverse-extracted with 2-butanone (30 ml). The organic layers were combined, which was washed by addition of an aqueous saturated sodium hydrogen carbonate solution (40 ml) and sodium chloride (7.00 g). Active carbon (0.3 g) was added to the organic layer, and the mixture was stirred at room temperature for 10 minutes. After active carbon was filtered, the organic solvent was distilled off under reduced pressure, acetonitrile (15 ml) was added thereto, and the mixture was heated to reflux for 40 minutes. The mixture was allowed to cool to room temperature for 1 hour, and water (9 ml) was slowly added dropwise. The mixture was stirred at room temperature for 30 minutes, and stirred at 0° C. for 30 minutes. The crystals were filtered and washed with cold acetonitrile/water=5/3(5 ml). The resulting crystals were dried under vacuum at 50° C. to give 6-(4-aminophenyl)-5-(N-benzyl-N-methylaminomethyl)-1-(2,6-difluorobenzyl)-3-phenylthieno[2,3-d]pyrimidine-2,4(1H, 3H)-dione (2.51 g, 4.23 mmol, 88.1%).

Provenance & Evidence