Construction
of Vicinal All-Carbon Stereogenic Centers
via Copper-Catalyzed Asymmetric Decarboxylative Propargylation: Enantio-
and Diastereoselective Synthesis of Substituted Spirolactones
posted on 2023-01-11, 13:41authored bySheng Zuo, Yuan Tao, Zhigang Liu, Ke Zhang, Luyun Zhang, Yingtang Ning, Fen-Er Chen
The formation of vicinal all-carbon quaternary stereocenters
remains
a formidable challenge. We report herein the synthesis of such highly
congested structural dyads by copper-catalyzed decarboxylative propargylation
between propargyl carbonates and indanone-based nucleophiles. The
implementation of diphenylethylenediamine (DPEN)-based ligands is
the key to success. A wide range of functional groups was tolerated,
delivering the indanone-based spirolactones in good yields with high
diastereo- and enantioselectivity. The mechanistic observations suggest
the capability of the new copper complex to enable stereocontrolled
addition to copper-allenylidene species.