171887-03-9Relevant articles and documents
Preparation method of 2-amino-4, 6-dichloro-5-formamidopyrimidine
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Paragraph 0054; 0062; 0067, (2020/12/30)
The invention provides a preparation method of 2-amino-4, 6-dichloro5formyl pyrimidine. The preparation method comprises the following steps: by taking malononitrile, formamidine or hydrochloride thereof as initial raw materials, carrying out nitrosation, formylation, cyclization, diazotization, Sandmeyer and reduction reaction to prepare the 2-amino-4, 6-dichloro-5-formamidopyrimidine. The preparation method disclosed by the invention is high in yield and high in product purity.
Method for Producing 2-Amino-4,6-Dichloro-5-Formamidopyrimidine
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, (2008/06/13)
The invention relates to a method for producing 2-amino-4,6-dichloro-5-formamidopyrimidine from 2,5-diamino-4,6-dihydroxypyrimidine or a salt thereof. According to said method, a) 2,5-diamino-4,6-dihydroxypyrimidine or the salt or tautomer forms thereof are reacted with a chlorination agent and a formamide of formula (I) wherein R1 and R2 independently represent a C1-C4 alkyl radical or —R1-R2— represents —(CH2)n— where n=4-6, or —(CH2)2-0-(CH2)2—, without adding a solvent, at a temperature of between 50 and 130° C., b) the reaction product obtained in step a) is reacted with water at a temperature of between 0 and 100° C., and regulated to a pH value of between 1 and 6 with an inorganic base, and c) the aqueous reaction mixture obtained in step b) is left to react at a temperature of between 70 and 120° C. under hydrolysis to form 2-amino-4,6-dichloor-5-formamidopyrimidine. The inventive method enables satisfactory yields and high levels of purity of the end product to be obtained. As a result of the significantly reduced reaction volumes due to the solvent, auxiliary substances and residual substances saved, and the significantly simplified method, the costs incurred in the production of 2-amino-4,6-dichloro-5-formylaminopyrimidine are significantly reduced.
Process for the preparation of 2,5-diamino-4,6-dihalogenopyrimidinen
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Page 5, (2008/06/13)
A halogenated hydrocarbon solvent is used in the production of 2,5-diamino-4,6-dihalo-pyrimidines (I) by reaction of 2,5-diamino-4,6-dihydroxy-pyrimidine (II) or its salts with a phosphorus oxyhalide and a quaternary ammonium halide. A halogenated hydrocarbon solvent is used in the production of 2,5-diamino-4,6-dihalo-pyrimidines of formula (I) by reaction of 2,5-diamino-4,6-dihydroxy-pyrimidine of formula (II) or its salts with a phosphorus oxyhalide and a quaternary ammonium halide. X = halo.