聚焦微波促进下碳酸二甲酯作甲基化试剂合成甲基取代的2-巯基吡啶并[2,3-d]嘧啶酮

Focused microwave-assisted synthesis of methylated 2-mercapto-7-arylpyrido [2,3-d] pyrimidin-4-(3H)-ones using DMC

在聚焦微波辐射下,氧化镁和四丁基溴化铵存在时,以二甲基亚砜为共催化剂,碳酸二甲酯作甲基化试剂,实现了2-巯基-5,7-二芳基吡啶并[2,3-d]嘧啶-4(3H)-酮的甲基化反应,并且可选择性地得到单甲基化和双甲基化的二芳基吡啶并[2,3-d]嘧啶-4(3H)-酮衍生物.结果表明,该甲基化方法具有产率高、时间短等优点.使用无毒的碳酸二甲酯代替碘甲烷或硫酸二甲酯作为甲基化试剂,避免了强碱和有毒试剂的使用,符合绿色化学的要求.

The methylation of 5-aryl-2-mercapto-7-arylpyrido [ 2,3-d] pyrimidin-4- （3 H）-ones promoted by MgO and TBAB under focused microwave using dimethyl carbonate as a non-toxic and environmentally friendly methylation reagent is described. The salient features of this method include comparably high yields and short reaction time. This protocol avoids the use of strong bases and highly toxic methylating agents such as methyl halide or dimethyl sulfate.