One-Pot Regioselective Synthesis of 2,5,6,7-Tetrahydroimidazo [1,2-a]imidazol-3-ones Starting from (Vinylimino)phosphoranes
作者:Fen Tan、Zheng-Zheng Meng、Xiao-Qin Xiong、Guo-Ping Zeng、Ming-Wu Ding
DOI:10.1055/s-0037-1611760
日期:2019.4
A new, one-pot, regioselective preparation of 2,5,6,7-tetrahydroimidazo[1,2-a]imidazol-3-ones by a sequential aza-Wittig/nucleophilic addition/cyclization reaction was developed. The aza-Wittig reactions of ethyl (2Z)-3-aryl-2-[(triphenylphosphoranylidene)amino] acrylates with aryl isocyanates produced carbodiimide intermediates that were then treated sequentially with 2-aminoethanol and tosyl chloride/triethylamine
2,5,6,7-四氢咪唑并[1,2-a]咪唑-3-酮通过连续的氮杂-Wittig/亲核加成/环化反应,开发了一种新的单锅区域选择性制备方法。(2Z)-3-芳基-2-[(三苯基亚膦基)氨基]丙烯酸乙酯与异氰酸芳基酯的氮杂-Wittig反应产生碳二亚胺中间体,然后依次用2-氨基乙醇和甲苯磺酰氯/三乙胺处理,得到相应的(2Z) )-2-[(取代的)亚苄基]-2,5,6,7-四氢-3H-咪唑并[1,2-a]咪唑-3-酮以良好的总产率和高区域选择性。