Direct (het)arylation of [1,2,4]triazolo[1,5- a ]pyrimidines: Both eliminative and oxidative pathways
作者:Nikolay A. Rasputin、Nadezhda S. Demina、Roman A. Irgashev、Gennady L. Rusinov、Oleg N. Chupakhin、Valery N. Charushin
DOI:10.1016/j.tet.2017.07.042
日期:2017.9
(Hetero)arylation of [1,2,4]triazolo[1,5-a]pyrimidine through the direct nucleophilic CH functionalization of the C-7 and C-5 positions has been implemented. The regioselective addition of a (het)aryl magnesium bromide to C-7 of 6-bromo-[1,2,4]triazolo[1,5-a]pyrimidine, followed by eliminative aromatization of the intermediate σH-adducts, has afforded 7-(hetero)aryl-substituted [1,2,4]triazolo[1,5-a]pyrimidines
[1,2,4]三唑并[1,5- a ]嘧啶的(杂)芳基化是通过C-7和C-5位置的直接亲核C H官能化实现的。区域选择性加入(杂)芳基溴化镁来的6-溴- [1,2,4]三唑并[1,5-C-7一]嘧啶,随后通过中间σ的消除性芳构ħ -adducts,具有得到7-(杂)芳基取代的[1,2,4]三唑并[1,5- a ]嘧啶(小号ñH反应,按照“加法消除”方案进行)。与格氏试剂的第二治疗导致了C-5σ ħ -adducts,这已被氧化,同时ñ -镁的盐为[1,2,4]三唑并[1,5一]嘧啶类,轴承的各种组合C-5和C-7(小号ñH过程,通过“加成-氧化”方案实现)。作为光学和电化学研究的结果,已证明所获得的化合物是有前途的发光染料和推挽系统。