4-Amino-3,5-pyridinedicarboxylates, of the formula:
wherein
R and R2 are independently selected from fluorinated and chlorofluorinated lower alkyl radicals; R is lower alkyl; R3 is independently selected from lower alkyl, cycloalkyl, and aralkyl are prepared by
(a) reacting an aretonediester of the formula
with a primary amine of the formula
to form an enamine;
(b) reacting the enamine with a carboxylic acid anhydride or halide of the formula
wherein X is
or a halogen to form a 2-alkylcarbonyl-3-amino-2-pentenedicarboxylate; and
(c) reacting the pentenedicarboxylate with a halogenated alkylnitrile of the formula
to form the 4-amino-3,5-pyridinedicarboxylate product
式中的 4-
氨基-3,5-
吡啶二
羧酸盐:
其中
R 和 R2 独立选自
氟化和
氯氟化的低级烷基; R 是低级烷基; R3 独立选自低级烷基、环烷基和芳烷基。
(a) 式中的质子
二元酯通过以下反应制备
与式中的
伯胺反应
生成烯胺;
(b) 使烯胺与式中的
羧酸酐或卤化物反应
其中 X 是
或卤素,生成 2-烷基羰基-3-
氨基-
2-戊烯二
甲酸酯;以及
(c) 将
戊烯二
甲酸酯与式中的卤代烷基腈反应
形成 4-
氨基-
3,5-吡啶二甲酸酯产物