139005-35-9Relevant academic research and scientific papers
Asymmetric Catalytic Formal 1,4-Allylation of β,γ-Unsaturated α-Ketoesters: Allylboration/Oxy-Cope Rearrangement
Tang, Qiong,Fu, Kai,Ruan, Peiran,Dong, Shunxi,Su, Zhishan,Liu, Xiaohua,Feng, Xiaoming
supporting information, p. 11846 - 11851 (2019/07/19)
A highly enantioselective formal conjugate allyl addition of allylboronic acids to β,γ-unsaturated α-ketoesters has been realized by employing a chiral NiII/N,N′-dioxide complex as the catalyst. This transformation proceeds by an allylboration/oxy-Cope rearrangement sequence, providing a facile and rapid route to γ-allyl-α-ketoesters with moderate to good yields (65–92 %) and excellent ee values (90–99 % ee). The isolation of 1,2-allylboration products provided insight into the mechanism of the subsequent oxy-Cope rearrangement reaction: substrate-induced chiral transfer and a chiral Lewis acid accelerated process. Based on the experimental investigations and DFT calculations, a rare boatlike transition-state model is proposed as the origin of high chirality transfer during the oxy-Cope rearrangement.
Enantioselective copper(I/II)-catalyzed conjugate addition of nitro esters to β,γ-unsaturated α-ketoesters
Zhang, Sheng,Xu, Kun,Guo, Fengfeng,Hu, Yanbin,Zha, Zhenggen,Wang, Zhiyong
supporting information, p. 979 - 982 (2014/02/14)
A highly enantioselective Michael addition of nitroacetates to β,γ-unsaturated α-ketoesters was developed by using chiral copper catalysts. The Michael addition products can be obtained in high yields with up to 99 % ee. With these densely functionalized products, the chiral cyclic nitrones, which are important synthetic intermediates, can be obtained in one step. Copyright
