Pd(II)-Catalyzed Asymmetric Oxidative 1,2-Diamination of Conjugated Dienes with Ureas.
Min-Song WuTao FanShu-Sen ChenZhi-Yong HanLiu-Zhu GongPublished in: Organic letters (2018)
A palladium(II)-catalyzed asymmetric 1,2-diamination of 1,3-dienes with readily available dialkylureas was established by using a chiral pyridine-oxazoline ligand. The diamination reaction exclusively occurs at the terminal C-C double bond of the 1,3-dienes to give 4-vinylimidazolidin-2-ones in high yields and with excellent levels of enantioselectivity (up to 99% yield, 97% ee). The reaction could feasibly be applied for gram-scale synthesis with a 1:1 ratio of the diene and the urea.