تفاعل #41161

معادلة التفاعل

(Tetrahydro-pyran-4-yl)-hydrazine hydrochloride

ethyl (ethoxymethylene)-cyanoacetate

sodium acetate

→

5-amino-1-(tetrahydro-pyran-4-yl)-1H-pyrazole-4-carboxylic acid ethyl ester

المردود 92.3%

المذيبات

ethanol

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةAfter cooling to room temperature
2. 2
   تركيزthe reaction was concentrated
3. 3
   أخرىthe residue was partitioned between methylene chloride and water
4. 4
   أخرىThe organic phase was separated
5. 5
   غسيلwashed with water
6. 6
   استخلاصEach aqueous phase was back extracted with methylene chloride
7. 7
   تجفيفdried over sodium sulfate
8. 8
   تركيزconcentrated in vacuo
9. 9
   أخرىThe crude material was purified by flash chromatography
10. 10
    غسيلeluting with 60-100% ethyl acetate/hexanes

الإجراء التجريبي

(Tetrahydro-pyran-4-yl)-hydrazine hydrochloride (1.975 g, 12.94 mmol), ethyl (ethoxymethylene)-cyanoacetate (1.958 g, 11.57 mmol) and sodium acetate (1.370 g; 16.70 mmol) were combined in ethanol (16 mL). The mixture was heated at 80-85° C. for 17 hours. After cooling to room temperature, the reaction was concentrated and the residue was partitioned between methylene chloride and water. The organic phase was separated and washed with water and then brine. Each aqueous phase was back extracted with methylene chloride. The two organic phases were combined, dried over sodium sulfate and concentrated in vacuo. The crude material was purified by flash chromatography eluting with 60-100% ethyl acetate/hexanes to give 5-amino-1-(tetrahydro-pyran-4-yl)-1H-pyrazole-4-carboxylic acid ethyl ester (2.554 g, 92%).

المصدر