Synlett
DOI: 10.1055/s-0043-1775428
synpacts

Visible-Light-Induced Enantioselective Dearomative [2+2]-Cycloaddition/Ring-Expansion Sequence of Indoles with Simple Alkenes

Liuzhen Hou
,
Longqing Yang
,
Xiaohua Liu
,
Weidi Cao
,
Xiaoming Feng
This work was supported by the National Natural Science Foundation of China (Nos. 22188101 and 92256302).


Abstract

Catalytic asymmetric dearomatization reactions represent a versatile platform for constructing complex optically active three-dimensional molecules. We present a visible-light-induced asymmetric dearomative [2+2] cycloaddition/ring-expansion reaction of indole derivatives with simple alkenes in the presence of a chiral N,N′-dioxide/terbium complex. This strategy provides access to a range of valuable cyclopenta[b]indoles, and its synthetic potential is further showcased through a gram-scale synthesis, potential bioactivity against human breast cancer, and further transformation into a yuehchukene analogue. A series of control and spectral experiments, as well as DFT calculations, provide compelling evidence to elucidate the reaction mechanism.



Publication History

Received: 18 September 2024

Accepted after revision: 03 December 2024

Article published online:
28 January 2025

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