4-Arylation of<i>N</i>-Acylamino- and Aminopyrazoles by the Suzuki-Miyaura Cross-Coupling Reaction
作者:Lukáš Jedinák、Petr Cankař
DOI:10.1002/ejoc.201600072
日期:2016.4
Halogenated aminopyrazoles have rarely been utilized in metal-catalysed cross-coupling reactions mainly due to the complexation of the aminopyrazoles to the metal center, which deactivates the catalyst. In this paper we reveal that the appropriate combination of palladium source and ligand enables efficient Suzuki–Miyaura cross-coupling reactions with even challenging substrates such as halogenated aminopyrazoles
卤代氨基吡唑很少用于金属催化的交叉偶联反应,主要是因为氨基吡唑与金属中心络合,这会使催化剂失活。在本文中,我们揭示了钯源和配体的适当组合可以实现有效的 Suzuki-Miyaura 交叉偶联反应,即使是具有挑战性的底物,如卤化氨基吡唑。Pd(OAc)2 和 XPhos 的组合允许卤代 N-乙酰氨基吡唑的有效偶联,而当使用未保护的氨基吡唑时需要 XPhos Pd G2。通常,卤化氨基吡唑与一系列芳基-、杂芳基-和苯乙烯基硼酸和酯发生容易的交叉偶联反应。所得联芳基、双杂芳基、