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ChemicalBook CAS DataBase List 2,4-Diamino-6-hydroxypyrimidine
56-06-4

2,4-Diamino-6-hydroxypyrimidine synthesis

7synthesis methods
-

Yield:56-06-4 95%

Reaction Conditions:

Stage #1:guanidine nitrate;ethyl 2-cyanoacetate with sodium methylate in methanol for 4 h;Reflux;
Stage #2: with hydrogenchloride in water; pH=9pH-value;

Steps:

1 Example 1: Preparation of DAHP
In a four-necked flask, 300 ml of methanol, 110 g of guanidine nitrate, and 55 g of sodium methoxide were heated and stirred for 1 hour.In the reflux state, methyl cyanoacetate was added dropwise. After refluxing for 4 hours, the recovered methanol was distilled off (applied), 800 ml of water was added, and the pH was adjusted to 9 with hydrochloric acid.Then, 50% of acetic acid was used to adjust pH=7, cooled to 5-10° C., filtered, washed with water and dried to obtain 120 g of DAHP dry product with a yield of 95% and a content of 99.1%.

References:

Jiangxi Kaiyuan Bio-pharmaceutical Technology Co., Ltd.;Xiangtan Kaiyuan Chemical Co., Ltd.;Chen Rongbing;Zhou Zhijun;Chen Luwu CN107857734, 2018, A Location in patent:Paragraph 0032; 0033; 0034; 0035

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