An Approach to Nonsymmetric Bis(tertiary phosphine oxides) Comprising Heterocyclic Fragments via the Pd-Catalyzed Phosphorylation
作者:Gladis G. Zakirova、Dmitrii Yu. Mladentsev、Nataliya N. Borisova
DOI:10.1055/s-0040-1706419
日期:2020.11
imidazole, and thiazole were synthesized in good yields via the successive introduction of phosphine oxide groups into the initial dihalogenated heterocycles by means of Pd-catalyzed phosphorylation reaction. The synthesis of pyridine-type compounds is hindered by competing double coupling, while for five-membered heterocycles the principal difficulty is the dehalogenation. Both side processes were successfully
通过连续引入氧化膦基团,以良好的收率合成了具有不同五元和六元杂环片段的非对称叔氧化膦,例如吡啶、2,2'-联吡啶、1,10-菲咯啉、喹啉、咪唑和噻唑通过 Pd 催化的磷酸化反应进入初始的二卤化杂环。吡啶类化合物的合成受到竞争性双偶联的阻碍,而对于五元杂环,主要困难是脱卤。通过使用过量的二卤化物(在产品纯化步骤中可以很容易地回收)、钯的合适膦配体和非极性溶剂(如甲苯)成功地抑制了这两个副过程。