Catalytic Michael/Ring-Closure Reaction of α,β-Unsaturated Pyrazoleamides with Amidomalonates: Asymmetric Synthesis of (−)-Paroxetine
作者:Yu Zhang、Yuting Liao、Xiaohua Liu、Qian Yao、Yuhang Zhou、Lili Lin、Xiaoming Feng
DOI:10.1002/chem.201603056
日期:2016.10.10
A highly enantioselective tandem Michael/ring‐closure reaction of α,β‐unsaturated pyrazoleamides and amidomalonates has been accomplished in the presence of a chiral N,N′‐dioxide–Yb(OTf)3 complex (Tf: trifluoromethanesulfonyl) to give various substituted chiral glutarimides with high yields and diastereo‐ and enantioselectivities. Moreover, this methodology could be used for gram‐scale manipulation
在手性N,N′-二氧化物-Yb (OTf)3配合物(Tf:三氟甲磺酰基)存在下,完成了对映体串联的α,β-不饱和吡唑酰胺和酰胺基丙酸酯的迈克尔/环封闭反应,得到各种取代基手性戊二酰亚胺,收率高,非对映和对映选择性高。此外,该方法可用于克级处理,并已成功应用于(-)-帕罗西汀的合成。进一步非线性和HRMS的研究显示,实际催化活性物质是一种单体大号-PMe 2 -Yb 3+络合物。提出了一个合理的过渡态来解释不对称感应的起源。