反应 #87885

反应方程式

Oxalyl chloride

5-(1-methyl-1H-pyrazol-4-yl)-2-naphthoic acid

guanidine hydrochloride

sodium hydroxide

→

5-(1-methyl-1H-pyrazol-4-yl)-2-naphthoylguanidine

收率 83.2%

溶剂

dichloromethane

反应条件

后处理

1. 1
   workup.ADDITIONwas added in portions during the reaction to effect dissolution))
2. 2
   温度The reaction mixture was then heated for 1 hour at 40° C.
3. 3
   浓缩before being concentrated under reduced pressure
4. 4
   workup.STIRRINGthe reaction mixture was then stirred for 30 minutes
5. 5
   其他The organic phase was separated
6. 6
   萃取the aqueous phase was extracted with chloroform (3×30 mL)
7. 7
   洗涤The combined organic extracts were washed sequentially with 1M aqueous sodium hydroxide (60 mL) and water (40 mL)
8. 8
   干燥dried (Na2SO4)
9. 9
   浓缩concentrated in vacuo
10. 10
    其他to give
11. 11
    其他a glassy solid (1.45 g after drying under high vacuum)
12. 12
    workup.DISSOLUTIONThis solid was dissolved in dichloromethane which
13. 13
    其他to evaporate slowly

实验过程

Oxalyl chloride (1.1 mL, 13 mmol) was added to a solution of 5-(1-methyl-1H-pyrazol-4-yl)-2-naphthoic acid (1.19 g, 4.71 mmol) in anhydrous dichloromethane (200 mL (which was added in portions during the reaction to effect dissolution)) containing dimethylformamide (2 drops) under nitrogen and the mixture was stirred at room temperature for 4.25 hours. The reaction mixture was then heated for 1 hour at 40° C., before being concentrated under reduced pressure. The resulting crude acid chloride was suspended in anhydrous tetrahydrofuran (50 mL) and this mixture was added dropwise to a solution of guanidine hydrochloride (2.09 g, 21.9 mmol) in 2M aqueous sodium hydroxide (15 mL, 30 mmol) and the reaction mixture was then stirred for 30 minutes. The organic phase was separated, and the aqueous phase was extracted with chloroform (3×30 mL) followed by ethyl acetate (3×30 mL). The combined organic extracts were washed sequentially with 1M aqueous sodium hydroxide (60 mL) and water (40 mL), then dried (Na2SO4) and concentrated in vacuo to give a glassy solid (1.45 g after drying under high vacuum). This solid was dissolved in dichloromethane which was then allowed to evaporate slowly to give 5-(1-methyl-1H-pyrazol-4-yl)-2-naphthoylguanidine as a yellow solid (1.15 g, 83%).

来源