Base-catalyzed cyclization reactions of 2-[2-(2,4-dimethyl-3-oxopentyl)]benzimidazoles with acetic anhydride and its homologs
作者:Siegfried Linke、Christian Wünsche
DOI:10.1002/jhet.5570100310
日期:1973.6
2-[2-(2,4-Dimethyl-3-oxopentyl)]benz, imidazoles (2-10) were obtained by allowing o-phenyl-enediamines to react with 2,2,4,4-tetramethyl-1,3-cyclobutanedione (1). When refluxed with acetic anhydride (or sterically unhindered homologs) they cyclize in the presence of base to yield the pyrido[1,2-α]benzimidazoles (16-21 and 24, 25). The 2-[2-(2,4-dimethyl-3-oxo-pentyl) ]imidazolines (12 and 14) were
通过使邻苯基-苯二胺与2,2,4,4-四甲基-1,3反应获得2- [2-(2,4-二甲基-3-氧戊基)]苯并咪唑(2-10)。-环丁二酮(1)。当与乙酸酐(或空间上不受阻碍的同系物)回流时,它们在碱的存在下环化,生成吡啶并[1,2-α]苯并咪唑(16-21和24、25)。通过使1,2-二氨基乙烷和1,2-二氨基丙烷分别与1反应,获得2- [2-(2,4-二甲基-3-氧代戊基)]咪唑啉(12和14)。当使其与乙酸酐/碱反应时,它们仅产生N-酰化产物。