Catalytic Asymmetric Michael Addition/Cyclization of Isothiocyanato Oxindoles: Highly Efficient and Versatile Approach for the Synthesis of 3,2′-Pyrrolidinyl Mono- and Bi-spirooxindole Frameworks
作者:Yi-Ming Cao、Fang-Fang Shen、Fu-Ting Zhang、Rui Wang
DOI:10.1002/chem.201204114
日期:2013.1.21
A‐spiro‐ing to greatness: The catalytic asymmetric Michael addition/cyclization of isothiocyanato oxindoles has been realized. This versatile approach provides an easy and highly efficient way to access not only the enantioselective synthesis of 3,2′‐pyrrolidinyl spirooxindole frameworks, but also the construction of enatiomerically enriched bi‐spirooxindoles containingthreecontiguous stereocenters
Regioselective
<scp>aza‐Michael</scp>
additions of
<scp>2‐arylidene</scp>
‐1,3‐diphenylpropan‐1,3‐diones with isatins: Synthesis of
<scp>N‐diketone</scp>
‐functionalized isatins
作者:Ya Cheng、Zheng Li
DOI:10.1002/jhet.4075
日期:2020.10
The efficient aza‐Michaeladditions of isatins to 2‐arylidene‐1,3‐diphenylpropan‐1,3‐diones at room temperature in the presence of cesium carbonate are described. The salient features of this protocol are no transition‐metal catalysts, mild conditions, high regioselectivity, high atom economy, satisfactory yield and simple work‐up procedures.