反应 #1694

反应方程式

1,4,5,6-tetrahydropyrimidine-5-carboxylic acid hydrochloride

oxalyl chloride

2-butyn-l-ol

→

5-(2-butynyloxycarbonyl)-1,4,5,6-tetrahydropyrimidine

收率 61.0%

溶剂

water

benzene

反应条件

后处理

1. 1
   温度heated
2. 2
   温度under reflux for 2.5 h
3. 3
   其他evaporated to dryness in vacuo
4. 4
   温度after cooling
5. 5
   其他to give an orange-yellow residue
6. 6
   workup.STIRRINGwas stirred at room temperature overnight
7. 7
   workup.STIRRINGAfter stirring overnight
8. 8
   其他the solvents were removed in vacuo
9. 9
   其他to give a brownish residue
10. 10
    workup.STIRRINGstirred at room temperature for 2 h
11. 11
    过滤filtered
12. 12
    其他The brown residue obtained on removal of the solvents in vacuo
13. 13
    其他was recrystallized (ethanol/ether)

实验过程

1,4,5,6-tetrahydropyrimidine-5-carboxylic acid hydrochloride (1 g, 6 mmol) was suspended in a solution of oxalyl chloride (1.5 mL, 17 mmol) in benzene (10 mL), heated with stirring under reflux for 2.5 h, and then evaporated to dryness in vacuo after cooling, to give an orange-yellow residue. A mixture of the acid chloride (04 g) and 2-butyn-l-ol (20 mL, excess) was stirred at room temperature overnight. After stirring overnight, the solvents were removed in vacuo to give a brownish residue. The residue was taken up in water (100 mL), stirred at room temperature for 2 h and filtered. The brown residue obtained on removal of the solvents in vacuo was recrystallized (ethanol/ether) to give a brown viscous oil (0.3 g, 61%) of 5-(2-butynyloxycarbonyl)-1,4,5,6-tetrahydropyrimidine as the hydrochloride salt. 1H NMR (D2O): δ 1.5 (t, 3H, CH3), 3.1 (m, 1H), 3.5 (d, 4H), 3.9 (q, 2H, OCH2), 7.9 (s, 1H, amidine-H). Anal. (C9H13N2O2Cl) C, H, N.

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