Suzuki-Miyaura cross-coupling of 3,4-disubstituted 5-bromoisoxazoles: An efficient access to trisubstituted isoxazoles
作者:Masato Tsuda、Taiki Morita、Hiroyuki Nakamura
DOI:10.1016/j.tetlet.2021.153185
日期:2021.7
The Suzuki-Miyaura cross-coupling of 3,4-disubstituted 5-bromoisoxazoles 1 at the C5 position has successfully proceeded in the presence of Pd2(dba)3 and P(t-Bu)3·HBF4 catalysts to give the corresponding trisubstituted isoxazoles 3 in good to high yields while suppressing the formation of ketone 4 as a byproduct. The use of bulky phosphine ligand P(t-Bu)3·HBF4 is essential for the current transformation
在Pd 2 (dba) 3和P( t- Bu) 3 ·HBF 4催化剂存在下,3,4-二取代5-溴异恶唑1在C5位的Suzuki-Miyaura交叉偶联成功进行,得到相应的三取代的异恶唑3 的产率很高,同时抑制了酮4作为副产物的形成。大膦配体P( t- Bu) 3 ·HBF 4的使用对于电流转化和酮4的形成是必不可少的上次报告中的主打产品,在目前的情况下能够被压制。