| 摘要 |
2-substituted 4,6-diamino-5-cyanopyrimidines of formula (I) wherein R1 is hydrogen, C1-C6alkyl, C2-C6alkenyl or C2-C6alkynyl and R2 is hydrogen, C1-C10alkyl or C3-C6cycloalkyl or R1 and R2 together are a radical, selected from the group of radicals, consisting of -(CH2)3-, -(CH2)4- and -(CH2)5-, are prepared by a process which comprises reacting a dialkyl cyanimidocarbonate of formula (V), wherein R3 is C1-C4alkyl, with an alkali metal salt of malononitrile or with malononitrile and an alkali metal base, at a temperature of -10 to +40 DEG C, to give a 1-alkoxy-1-cyanomino-2,2-dicyanoethylene alkali metal salt of the formula (IV), wherein R3 is C1-C4alkyl and M<+> is an alkali metal cation, reacting this compound with an excess of ammonia at a temperature of 60 to 110 DEG C to give a 1-amino-1-cyanamino-2,2-dicyanoethylene alkali metal salt of formula (II), wherein M<+> is an alkali metal cation, reacting this salt with excess hydrogen chloride in a secondary alcohol, water or a mixture thereof as solvent to give 2-chloro-4,6-diamino-5-cyanopyrimidine, and then reacting this compound with an amine of the formula R1R2NH to give the final product. |
