تفاعل #65930

معادلة التفاعل

calcium carbonate

sodium nitrite

3-Dipropylamino-5-aminochroman

trifluoracetic acid

Sodium nitrite

→

title compound

3-Dipropylamino-5-nitrochroman

المذيبات

water

water

water

water

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةThe clear solution was cooled to 0°-4° C
2. 2
   workup.STIRRINGThe solution was stirred at 0° C. for 20 minutes
3. 3
   workup.WAITat ambient temperature for 2 hours
4. 4
   استخلاصThe solution was extracted with diethyl ether
5. 5
   تجفيفThe organic phase was dried with sodium sulfate
6. 6
   أخرىevaporated to dryness
7. 7
   أخرىThe residue was purified by flash chromatography on silica gel by elution with ethyl acetate/hexane 1:9

الإجراء التجريبي

3-Dipropylamino-5-aminochroman (Example 14; 0.050 g, 0.20 mmol) was dissolved in a mixture of trifluoracetic acid (0.080 ml, 1.0 mmol) in water (5 ml). The clear solution was cooled to 0°-4° C. Sodium nitrite (0.017 g, 2.5 mmol) in water (1.0 ml), was added dropwise with good stirring. The solution was stirred for 15 minutes and neutralized with calcium carbonate. A solution of sodium nitrite (0.50 g, 7.2 mmol) in water (1.0 ml) was added followed by a mixture of copper sulfate (0.10 g, 0.62 mmol) and copper (1) oxide in water (1.0 ml). The solution was stirred at 0° C. for 20 minutes and then at ambient temperature for 2 hours. The solution was extracted with diethyl ether. The organic phase was dried with sodium sulfate and evaporated to dryness. The residue was purified by flash chromatography on silica gel by elution with ethyl acetate/hexane 1:9 to give the title compound. Mp 150°-151° C. (hydrochloride).

المصدر