تفاعل #214374

معادلة التفاعل

2-methoxy-5-cyanopyridine

semi-carbazide hydrochloride

sodium acetate

ethanol

→

6-methoxypyridine-3-carboxaldehyde

المردود 50.3%

المذيبات

water

ظروف التفاعل

المعالجة

1. 1
   أخرىThe mixture was evaporated to a volume of 500 ml, water (1,000 ml)
2. 2
   workup.ADDITIONwas added
3. 3
   ترشيحThe mixture was filtered
4. 4
   غسيلthe solid was washed with water
5. 5
   workup.DISSOLUTIONdissolved in 10% hydrochloric acid (1,000 ml)
6. 6
   workup.ADDITIONFormaldehyde solution (36% w/v, 450 ml) was added
7. 7
   درجة الحرارةthe mixture was warmed for 15 minutes
8. 8
   درجة الحرارةto cool
9. 9
   workup.ADDITIONwas added to a solution of sodium acetate (298.5 g) in water (900 ml)
10. 10
    استخلاصThis mixture was extracted with ether
11. 11
    غسيلthe combined extracts were successively washed with aqueous potassium carbonate and water
12. 12
    أخرىwere dried
13. 13
    أخرىevaporated

الإجراء التجريبي

A mixture of 2-methoxy-5-cyanopyridine (61.26 g), semi-carbazide hydrochloride (76.4 g), sodium acetate (74.92 g), ethanol (1,300 ml) and water (400 ml) was hydrogenated at 344 kPa using Raney nickel catalyst (1.0 g). The mixture was evaporated to a volume of 500 ml, water (1,000 ml) was added and the mixture was allowed to stand at 0° overnight. The mixture was filtered and the solid was washed with water and dissolved in 10% hydrochloric acid (1,000 ml). Formaldehyde solution (36% w/v, 450 ml) was added and the mixture was warmed for 15 minutes, allowed to cool and was added to a solution of sodium acetate (298.5 g) in water (900 ml). This mixture was extracted with ether and the combined extracts were successively washed with aqueous potassium carbonate and water and were dried and evaporated to give 6-methoxypyridine-3-carboxaldehyde (31.5 g, 50%), m.p. 48-49°.

المصدر