An I2-mediated annulation of 2-amino[1,3,5]triazines and ketones for the synthesis of imidazo[1,2-a][1,3,5]triazines is presented. Electron rich, or electron poor acetophenone and heterocycle ketones, as well as propiophenone, are functionalized with 2-amino-[1,3,5]triazines. Another class of imidazo[1,2-a][1,3,5]triazines tethered with an additional 1,2-dicarbonyl motif through the combination of annulation and C–H functionalization were obtained instead by changing the reaction conditions. The new methods are practically straightforward and applicable on a gram scale.
![Graphical abstract: Diversity-oriented synthesis of imidazo[1,2-a][1,3,5]triazine derivatives from 2-amine-[1,3,5]triazines with ketones](http://hg.y866.cn/compound/lib/scimg/usr/1/D1CC04294G.jpg)