Liu Yuxin, Wei Zhonglin, Liu Yu, Cao Jungang, Liang Dapeng, Lin Yingjie, Duan Haifeng
Department of Chemistry, Jilin University, Changchun, Jinlin Province, China.
Org Biomol Chem. 2017 Nov 7;15(43):9234-9242. doi: 10.1039/c7ob02501g.
New quaternary ammonium types of bifunctional asymmetric phase-transfer catalysts bearing multiple hydrogen-bonding donors derived from α-amino acids were readily prepared and found to be highly efficient in the asymmetric nitro-Mannich reactions of amidosulfones. Very broad substrate generality was observed, and the products were achieved in high enantio-/diastereoselectivities (90->99.9% ee, 90 : 10 to 92 : 8 dr). Compared with previous reports, the enantioselectivity of aliphatic amidosulfones has been improved to a high level (91-93% ee).
新型季铵型双功能不对称相转移催化剂很容易制备，该催化剂带有多个源自α-氨基酸的氢键供体，并且发现其在氨磺酰的不对称硝基-Mannich反应中具有很高的效率。观察到底物具有非常广泛的通用性，并且产物具有高对映体/非对映体选择性（对映体过量值为90->99.9%，非对映体比例为90 : 10至92 : 8）。与之前的报道相比，脂肪族氨磺酰的对映选择性已提高到较高水平（对映体过量值为91-93%）。
