Several pyrimido[4,5-b]quinolines, flavin analogues, have been prepared by assisted microwave intramolecular cyclization of N4-substituted-2,4-diamino-6-chloropyrimidine-5-carbaldehydes. The reaction takes place with hydrolysis of amino-group and chlorine. Particularly valuable features of this method included the broader substrate scope and operational simplicity as well as increased safety for small-scale
通过N 4取代的2,4-二氨基-6-氯嘧啶-5-甲醛的微波辅助分子内环化反应,已经制备了几种嘧啶[4,5- b ]喹啉,黄素类似物。该反应在氨基和氯的水解下进行。该方法特别有价值的特征包括更宽的基板范围和操作简便性,以及用于小规模高速合成的更高的安全性。
Microwave-assisted synthesis of pyrazolo[3,4-d]pyrimidines from 2-amino-4,6-dichloropyrimidine-5-carbaldehyde under solvent-free conditions
The microwave-induced synthesis of pyrazolo[3,4-d]pyrimidines 4 in the reaction of N4-substituted-2,4-diamino-6-chloro-5-carbaldehydes 3 with hydrazine is described here. Precursors 3 have been prepared by the mono-amination of 2-amino-4,6-dichloropyrimidine-5-carbaldehyde 2 with aliphatic and aromatic amines. The reaction times with primary amines were relatively shorter than for secondary amines
这里描述了在N 4-取代的2,4-二氨基-6-氯-5-甲醛醛3与肼的反应中微波诱导的吡唑并[3,4- d ]嘧啶4的合成。前体3是通过2-氨基-4,6-二氯嘧啶-5-甲醛2与脂族和芳族胺的单胺化反应制备的。与伯胺的反应时间相对短于仲胺。